Generally good and bad practices (and mindsets!)
Designing a Pokémon is an iterative process, not a cumulative one!
This goes hand in hand with the above advice about stats - pretty often, I see someone come into #submission-feedback with a fully-formed idea and receive negative feedback, then respond as though it's a ton of work to throw an idea away and "start over" now that they know they need to change something about it. This is especially common when people find that their direction isn't widely appealing or that it overlaps too much with another sub, so they may well need to rethink it from its core to make something worthwhile.
Admittedly, I can totally understand why someone would find that frustrating at times! But this...
really strikes me as the wrong mindset to have when coming up with ideas, and it seems like it usually makes people enjoy the process of submitting less. There is no better way to come up with a good idea than to change your approach - you need to be willing to let go of your first ideas and try new ones instead of trying to hold onto as many details as possible!
I don't think anyone consistently comes up with great ideas on the first try - at least for me, coming up with a solid premise for a Mega Evolution is
always something I do over and over again if I make a sub at all, and only about a third of my ideas even make it to the thread.
Personally, I find that stats, types and move additions all usually fall together pretty straightforwardly once I'm satisfied with an idea (which is a big part of why I personally emphasize Abilities and unusual roles the most), and type changes and move additions aren't even something you need to decide unless something about your idea makes you want them - there are plenty of great submissions that don't change either! If you struggle in those areas, there's pretty much always someone in #submission-feedback who can help you through them; the important thing here is the creative process of exploring your ideas and finding the one that clicks, not to do homework and spend ages refining stats.
And hey, if doing stats stresses you out, you can always just not do them until after you're sure of an idea!
Reiterating: do stats last! The earlier in your creative process you open up to ask for feedback, the less there is to do over if you change your mind.
I cannot stress enough that nothing is more important than being comfortable with exploring more than one route and finding the one that works best. Even if you end up sticking with your first option, at least you know then that you considered other options and it's really your favorite!
When you're using an Ability that's already on another Mega, try to do something new with it!
We're totally open to using the same Ability twice - even with custom Abilities! Our
Mega Typhlosion borrows the Ability Ignite from
Mega Toucannon, for example, and although it didn't turn out to win, one particularly well-thought-out Magcargo submission borrowed Counter-Clockwise Spiral from
Mega Slowking.
That said, it's best to avoid doing this without a specific reason - a selling point that
relates to the Ability that the other Pokémon doesn't have.
In
some cases, just being a different type can be enough to set two Pokémon apart - the important thing is to consider
why its type matters and what it has to do with the Ability, not just to have different coverage for the sake of it.
For example, a Water-type attacker with Primordial Sea would be completely different from
Mega Dhelmise - not just because it's a different type, but because both of their types have something to
do with Primordial Sea. Being a Ghost/Steel-type is a big part of the reason Dhelmise wants Primordial Sea, since it's normally weak to Fire and the Ability directly contributes to its defensive utility; a Water-type would already resist Fire and doesn't really care about that, but it's carried further offensively with the Ability's boost to its STAB.
In this case, despite having the same Ability, their types capitalize on different parts of it.
Notice that introducing a new Water-type with Primordial Sea doesn't encroach on what makes Dhelmise worth using, because it's the Ability in combination with different other qualities that makes each of them worthwhile.
This is important! We make a serious effort to keep our Mega Evolutions' niches distinct where possible, so if we already have a Mega Evolution that does something unique, we broadly try to avoid making anything that will
directly outclass it or compete with it at doing exactly the same thing.
A case when this
doesn't work is the example I brought up earlier: Mega Zoroark sharing Masquerade with Mega Hawlucha.
When I asked what would set them apart, it was pointed out that Zoroark had a different type and that it was a special attacker instead of a physical attacker (and had Nasty Plot rather than Swords Dance by extension).
The problem here is that none of these factors
relate to the Ability - their roles are still the same (both are fast, frail attackers), and while it was previously brought up that the type combination of Fighting/Flying and a preference for physical moves are both advantageous for Masquerade, mono Dark and a special bias have no such advantages; there are no widespread Abilities that work with those qualities that Hawlucha can't also use
(notably, the only Ability that directly powers up Dark moves - Dark Aura - is exclusively found on other Mega Evolutions and Ubers, so there would be no way for Mega Zoroark to capitalize on its type with even one legal Ability).
In other words, Masquerade Zoroark doesn't bring anything new to the table; even if Zoroark has superficially different qualities from Hawlucha, they mostly pair poorly with Masquerade, and the only value of putting the Ability on Zoroark is its flavor. This is a case where overlap like this would be unwelcome; it squanders the potential of a Mega Zoroark, and there's not a clear reason why more than one Pokémon warrants Masquerade when the result is only one of them using it effectively.
With the above in mind, keep in mind to choose the right Pokémon for the job - and be willing to step back and save an idea for later if that's not a part of the current slate!
This is especially true when you're introducing a new effect or a custom Ability!
If you have an idea for a custom that's particularly original and innovative, or an Ability that creates a niche in itself, it can be easy to think that that's all you need and to stop there.
It's true that there
are some Abilities that have interesting effects on their own and would serve the same purpose no matter what had them; in some cases, these could be considered the main reason to use a given Mega Evolution on a team. Examples would be Pokémon like
Mega Orbeetle (sets Gravity on entry),
Mega Delibird (restores items to the team on entry) and
Mega Chandelure (curses the attacker when defeated, then permanently transfers this Ability to the attacker). The most important thing to remember is that
the Pokémon with the Ability still matters!
If the entire reason to use a Mega is for its Ability's effect in a vacuum, but it's not designed well around that Ability, then that has a couple of consequences that aren't great - it means it's not very good at its job and might be hard for it to see use, but it also means we won't have the opportunity to add another Pokémon setter later, because it would be hard to avoid leaving the original behind and letting it be outclassed.
Let's use the Ability
Gravitas as an example, because it's been brought up for more Pokémon in the past than just the one that has it now - I think it's an excellent example of how not only
being on the right Pokémon but being on the right Pokémon
first was crucial to
Mega Orbeetle's success, and what might have gone differently if someone else's beat it to the punch.
At a glance, Orbeetle might look like it's kind of a surface-level pick for an Ability that sets Gravity - the flavor connection is already there, because its Gigantamax has the very same effect and its design is based on tractor beams, so one might assume that that's all there was to the decision.
This isn't true at all, though!
People have also proposed autosetting Gravity as an Ability for other Pokémon, like Lunatone, in the past, but there are numerous factors that make Mega Orbeetle
the ideal user of Gravitas, and none of the others come close to living up to it. The Gravity field effect has two primary effects - one of them is to force non-grounded Pokémon to the ground, making them susceptible to Ground-type moves and grounded entry hazards, and the other is to increase the accuracy of moves by 5/3 (such that a 60%-accurate move becomes 100% accurate).
Mega Orbeetle is equipped to capitalize on each of these in multiple ways.
Orbeetle, even before the submission modified it, came with an excellent type and movepool for Gravity, and it was well chosen as a candidate by both Game Freak and Scoopapa
personally I'm inclined to give Scoopapa the credit here, because the very mechanic of Gigantamax stops the official G-Max Orbeetle from making the most of this anyway. Orbeetle is already capable of setting a grounded entry hazard itself, so Gravity takes away the immunity non-grounded Pokémon have the threatening Sticky Web and enables ally sweepers a great deal more; in addition, it already comes with the 60%-accurate Hypnosis, which Gravity turns into the most reliable sleep move in the game - 100%-accurate like Spore, but without being powder-based so even Grass-types can't stop it; and while Gravity is known for making Ground-types substantially more dangerous, Orbeetle already comes with one of the only two types that can still switch in on Ground-type moves, so its type is one that would be necessary on any team with Gravity to keep its opponents from turning the field against it.
The main changes Scoopapa made in his submission were to add Teleport (a pivoting option that's often more optimal than U-turn, the one Orbeetle already had, for a supportive role) and Focus Blast (an attacking move that both benefits from Gravity and complements Bug/Psychic STAB incredibly well); both of these changes are focused on making Orbeetle better at its job and on pairing with its Ability, but they're also obviously fitting choices for it and certainly don't feel like forcing it to be something it's not!
It's easy to see why Orbeetle was perfect for this, and the resulting submission is brilliantly designed around benefiting from such an Ability and making it feel as good as possible to build around it.
But uh... what would happen if we did something else
before Orbeetle? If Mega Orbeetle didn't already exist, then when Lunatone's slate came around, someone might well have submitted a Lunatone with this same Ability (not an arbitrary example! this idea has been brought up before by someone who didn't know about Mega Orbeetle), and it might well have won! Autosetting Gravity
is a novel and interesting idea that has a great deal of supportive potential in a vacuum, no matter how good or bad Lunatone itself may be at exploiting it. But it would have won on the grounds of
its Ability being something people want, and that's not necessarily the same as
that Mega Lunatone being a well-executed idea.
A Pokémon like Lunatone would have been put in great danger by its own field effect - bringing its own weakness to Ground and nullifying its own team's safest switch-ins against Ground-type moves would have made it difficult to build a team around it, and it would be easy to punish Lunatone by bringing in a Ground-type against it right away - and its only entry hazard is one that already works on non-grounded Pokémon. While it could be argued that Lunatone could at least exploit Gravity offensively, it
already covers the few Pokémon that resist its Rock- and Ground-type coverage thanks to its STAB Psyshock, and a simpler Ability like Mold Breaker would have been just as effective at bypassing Levitate on Pokémon like Bronzong, without the major drawbacks of enabling its own weaknesses
or needlessly introducing a brand-new Ability it can't use well and taking the associated niche from other Pokémon that are more deserving.
Basically, the Ability is cool, but Lunatone is not at all the Pokémon for it.
Often, this kind of ground
can be covered with type, stat and movepool changes - but we do have rules for all of those, and there's also a matter of making basic flavor sense and being palatable to the voters, so people (understandably!) aren't always willing to go all that far in these areas to force their Pokémon to be something it's not.
This is when choosing the wrong Pokémon for the job becomes a problem: when trying to stay true to the Pokémon is an
obstacle in the way of making an idea work
for example, the only way for Lunatone to keep one of its types and resist Ground under Gravity like Orbeetle would be to replace Rock with either Grass or Bug, neither of which particularly suits it and one of which just emphasizes that Orbeetle is the better choice,
please wait for another Pokémon rather than trying to be the first one to get to the idea!
Whether you get there by changing a lot about the Pokémon or by picking a candidate that already works, the absolute most important thing is to end up with a Pokémon that's
both flavorful and practical, not just an aesthetic judgment that it would suit it to use Gravity.
If Lunatone did win, then... how would we ever get to introduce a
good Gravity setter later? If the one thing that makes Mega Lunatone worth using is the fact that it sets Gravity for its teammates' sake, and it's barely even good at it, there's no way at all that it would still be used if we later gave it a competitor that was effectively designed around doing the same thing.
That means our fantastic Orbeetle could probably not even have been
allowed to exist. In line with what I said in the last section about trying to use Abilities in new ways without outclassing the Pokémon that already have them, well... if someone comes along later with a Mega Orbeetle that does everything Lunatone does and then some, those aren't going to be able to coexist - if we allowed that, it would be a waste of our Mega Lunatone.
We'd then be stuck with a cool-on-paper Ability on a Pokémon that can only barely use it, and a much better application of the idea would have had to be passed up on - if we have to keep Lunatone as "the" Gravity setter, because it's entirely carried by that idea's novelty and that's the one thing it has going for it, then we can't
afford to do anything better with the idea or Lunatone would become pretty much pointless!
So this is what I mean about "saving" good ideas and considering when to use them - we don't want to close those doors just to get the idea down as soon as possible. The more potential an idea has in a vacuum, the more there is to lose if we actually treat it like it's in a vacuum!
(Remember this, too: we have several hundred Mega Evolutions to go!! You don't need to feel pressured to submit all of your good ideas as soon as they come to you, and I really strongly encourage saving them for when they're best spent.
This also goes along with what I said about field effects - there's a reason Orbeetle makes such a good example of this! It highlights just how much more goes into making a field effect
setter work than just whether or not the field effect itself is a good idea in a vacuum.)
I know this section was a super long ramble, but here's the tl;dr of it!!
If you're submitting an idea, especially a custom Ability, you should ask yourself, "Why does this effect belong on
this Pokémon?"
It might be that the Pokémon is optimized as well as it could be to bring the idea to fruition, like in the case of Orbeetle. Or it might be that the Pokémon isn't perfect, but the idea addresses some of its specific flaws and the effect is more relevant to helping that Pokémon than it might be to others (again, while part of the problem with Lunatone is that it doesn't serve the part of Gravity setter well, the other part is that Gravity doesn't do anything
for it that another regular Ability like Mold Breaker wouldn't!). Either way, there's some kind of
connection in their mechanics - either some reason the Pokémon is better off with this idea than almost any other Ability or some reason the idea is better off with this Pokémon than with almost any other Pokémon.
In Scoopapa's case, the answers must have come easily: "Sticky Web, Hypnosis, relevant Ground resistance
and explicit flavor connection" - there's really no question that Orbeetle deserves Gravitas!
But if the Lunatone slate came around first, and you had this same idea for an Ability and asked yourself "Why does Lunatone need Gravitas?" and didn't have any answer except that it's kind of space-y and looks about right... that's the kind of idea that you should
save instead!
The perfect opportunity will come along eventually - it doesn't have to be for whatever the current slate is now.
Be very careful with weather-reliant Abilities
Among other features of Mega Evolution as a mechanic, one important quality is that you only use one on a team.
This means that directly competing with other Mega Evolutions is often detrimental, and never is this more important to have in mind than when making a Mega Evolution that relies on a specific team style, like weather.
For example, rain-reliant Mega Evolutions are almost always a bad idea. Rain as a team style relies heavily on Mega Swampert, a Pokémon that has fantastic synergy with other rain setters and users because of its unique type. It's invaluable defensively for its Electric immunity; offensively for its Ground STAB (which handles many of rain's usual checks) and Water STAB (which benefits directly from rain) and its Ability, Swift Swim, probably the best rain Ability that exists in canon; and even supportively, enabling rain teams to set Stealth Rock and excelling at the part because it can handle Mega Sableye reliably. Mega Swampert is
optimized around being
exactly what rain needs in every way.
We tried making a Swift Swim Mega Evolution in the past with
Mega Walrein, but even with the same Ability that made Swampert so threatening, great bulk, perfect coverage and reliable recovery... it
still wasn't worth using, because rain teams kind of can't live without Mega Swampert. We eventually yielded and gave it a different Ability to make it self-sufficient and usable on teams that weren't otherwise committed to rain, and even though the loss of Swift Swim basically meant cutting its Speed in half under ideal circumstances, that
improved it significantly.
Pay attention to what Pokémon already have a place on weather teams, Mega or not, and be aware of how they compete with yours - if there's already a better Mega to use on a given team style, it might not be affordable to spend the Mega slot on your new take, and if there's already a more important Pokémon to the style that overlaps with yours in type and role, it might also be harder to fit your idea onto a team (see also:
Mega Aurorus needed to be reworked in no small part because it shared a type with Arctozolt - it was always better to run Arctozolt with
Mega Regice than to give up both an important Ice/Electric and an important hail Mega to fit Aurorus).
It's also worth paying attention to what Mega Evolutions the mod has already introduced! It's widely believed that sun just has
too many Megas at this point (in addition to the canon
Mega Charizard Y and
Mega Houndoom, M4A already has
three more that use sun in different ways -
Mega Meganium,
Mega Gigalith and
Mega Sawsbuck-Summer, the last of which is itself almost two in one because of its flexible Ability gimmick), and many people have voiced that they aren't really itching to see more; rain has more or less been unfeasible to top from the start thanks to Swampert; and Mega Regice has been considered the only reason hail is even viable in this meta of ours, so there's a dangerously high bar for any competing additions. Sand is probably the only kind of weather Mega that people are likely to welcome with open arms, and even then, opportunities to do what sand needs are limited.
In short:
don't use weather Abilities lightly! It's super rare that a weather-based Mega Evolution is actually called for, and while some people have done them well (part of why so many people wanted Sand Rush Cacturne last slate was because its type was actually important to sand teams - there are few relevant sand Mega Evolutions competing with it and specific reasons why Cacturne would be good for the part), it's something to avoid unless you
really know what you're doing; weather-reliant Megas have been found to be flawed premises and needed reworks and buffs more than once in our mod's history, and it's rarely worthwhile.
A quick followup note on the same topic: it's also not usually a great idea to make a Pokémon that relies too heavily on its base form's Ability, which is something that people attempt often for Pokémon whose
base forms set field effects (an example of this would be making a Mega Rillaboom and giving it Grass Pelt, since it has Grassy Terrain for "free" and can use it right away).
Some archetypes
can work with this - for example, a Pokémon that's meant to be a fast lategame cleaner and
isn't intended to switch out once it's doing its job can operate effectively under these circumstances, which is frequently the case for Pokémon designed around Speed Boost - but it's important to note that most Pokémon will eventually have to switch out, and it's generally really, really bad if leaving the field is just a death sentence for it.
This has been circumvented in the past in a few ways:
Mega Rillaboom continues to rely on Grassy Terrain, but it doesn't lose the means to set it, as its new Ability also sets Grassy Terrain in a unique way;
Mega Gigalith is designed around a field effect that its base form
can't set, discouraging it from running Sand Stream in the first place and allowing it to be balanced around the assumption of no sand;
Mega Vanilluxe and
Mega Aurorus both set field effects themselves, but not (necessarily) the same ones as their base forms; and the canon
Mega Tyranitar and
Mega Abomasnow simply keep their base forms' weather-setting Abilities and do their best to work with them in a new way, Tyranitar being a "sidegrade" through a stat spread that creates a different role than any other held item and Abomasnow by using a smart stat distribution to succeed exactly where its base form failed.
At least personally, I'm of the opinion that playing with hypothetical combinations like "Drought Ninetales -> Solar Power
Mega Ninetales" is an unwise decision, because it's basically impossible for the Pokémon to be effectively balanced both during its five turns of sun and after they wear off; with as drastic a difference as there is between the two states, it's highly likely that any version that isn't outright broken during its first five turns will be dead weight for the remainder of the battle. For example, a Mega Ninetales with Solar Power would
need to be substantially weaker than any non-Drought Mega Evolution would be (compare Houndoom, for example) to make up for its lack of needed support... but then after its first five turns, a Pokémon that's substantially weaker than Mega Houndoom out of sun will still probably want sun support, and then it would be that much harder to justify running it over Mega Houndoom in the first place. There's a delicate balance to strike, as the advantage is both far too big to be taken lightly and too short-lived to justify running without the proper support, so it's rarely feasible to balance effectively and a route I really strongly advise against.
Being the strongest or being broken on purpose is not a selling point! And neither is "I hate stall, so here's how you never have to worry about it again!"
To some of you, this might sound like stating the obvious - if that's the case, you're probably fine and you don't need to worry about this! I'm perfectly serious when I say that this is only a problem when people do it on purpose, and that ideas like this have been submitted more than once.
We strive to create a balanced metagame, and to us, that means
being friendly to a wide variety of team styles (yes, even stall!!) and
having a wide variety of viable Pokémon. When a Pokémon turns out to be too dominant or oppressive to specific team styles (or, on the other hand, when it's greatly struggling to do its job and isn't usable), we regularly make balance changes to address that!
With this in mind, consider the simple fact that
brokenness isn't permanent - if your Pokémon really is a bonkers sweeper that stall can't beat, we won't just leave it sitting there, and it will be nerfed sooner or later until it's no longer broken.
People who aren't used to building for a meta like this sometimes consider it a service to the metagame and to other players to create something that "kills stall," often just by making an incredibly hard-hitting attacker that can't be walled. However, this is
contrary to our goals and
is not a good thing - if it really is as good at that as you think, we just... won't allow it.
Naturally, if your Pokémon does something
unique and interesting, any future balance changes will obviously be aimed at preserving and amplifying that! But raw power is something we're constantly reevaluating, and no Pokémon has any "right" to be the
perfect setup sweeper or the
perfect wallbreaker, nor does any submitter have any "right" to pick and choose what team styles are viable in the mod as a whole.
Some people really like playing defensively - it's actually
not a good thing to make something that destroys stall as a playing style just because you want the game to be more fast-paced, because that would ultimately shut down a lot of other players and stop them from having fun, or even turn the game into rock-paper-scissors ("this Mega always beats stall, this Mega always beats offense, and this Mega always beats balance" - that is... if you see your opponent's Mega Evolution at team preview and you're playing the wrong kind of team, you might as well just lose on the spot). At that point, why are any of us even playing? In the long term, this is
bad for a metagame.
That said, it's totally possible for this to happen accidentally, and there's nothing wrong with that! People make mistakes all the time - my
own Mega Slowking had too good a matchup against hyper offense teams, for example, and all we had to do was nerf it later on. Because that wasn't the
point of Mega Slowking - because there was more to it than just "a Pokémon whose job is to end hyper offense" - it's still doing fine even after being nerfed and taking its place as a healthier part of the mod, and the idea that made it unique (its Ability) is still perfectly intact. Just like with Slowking, it's totally okay if you don't balance your idea perfectly on the first try!
But there's a
huge difference between a case like Slowking and making something broken
on purpose. I've seen a lot of submissions that are quite explicitly aimed at ending stall so that games are faster for the one using them, and that's the entire goal of the submission. That's the kind of Pokémon that (if it even works) gets either vetoed on the spot or nerfed - and if its entire identity rests on it being broken, what would be the point of having it when it's not broken any more?
A common mistake I see on this front is when people confuse
restraint for
lack of foresight - like, a ton of official Mega Evolutions are criticized for wasting stat points and not spending their +100 BST optimally. (Or maybe a Mega Evolution would be
better with this great coverage move or this great setup move - how could you
forget to give it that?)
For example, when X and Y came out, there were many comments that criticized Mega Gardevoir for raising its Attack, which it obviously didn't need - as though some misguided soul at Game Freak thought raising Attack was more important than Defense or even Speed. But in Generation VI, Mega Gardevoir turned out to be OU in Smogon's terms and was perfectly useful in Game Freak's official formats, BSS and VGC. In actuality, it's not that Attack was considered
more important than Defense or Speed or that anyone thought those 20 points would be useful, but that its maker
didn't want to raise Defense or Speed and that it
didn't need to be stronger.
Knowing when to show this kind of restraint is crucial - not every Mega Evolution
should make full use of all 100 of its stat points, and knowing
how hard you want to hit,
how fast you need to be and
how well you need to take hits is always more valuable (and shows more thoughtful design) than knowing the
strongest way to spend all 100 points you're given.
The most popular submissions are usually the ones that are creative and well thought out but kept in check by having no better stats than they need - not the other way around!
To close off this section, here's a fun fact: remember what I said about
Mega Slowking?
Mega Slowking's Ability sets Trick Room for as long as it remains in battle, but it wears off when Slowking leaves like Primordial Sea - the idea was to prevent it from being used supportively, which would be super dangerous on almost anything, but especially so with Slowking's access to Teleport.
This is still an obviously powerful effect for a slow Pokémon, so at first, recognizing how strong it was on its own, I tried to keep it in check by putting 55 of its 100 points into its Speed - not only squandering them but making it actively worse, since its Ability is better on a slow Pokémon.
As mentioned, Slowking later had to be nerfed. In its later incarnation, its Speed was increased
further - from base 85 to base 120, spending no fewer than
90 points of its precious +100 BST on a stat that was not just useless but actively detrimental to it.
It's still strong as heck.
A Mega Slowking that used its +100 BST "well" - let alone
optimally - would be broken beyond belief!
In hindsight, perhaps Slowking was not the safest choice for an Ability like this in the first place, haha - but if this case tells us anything, there's no denying that throwing away points
can be the right choice, and sometimes you don't need anywhere near the 100 points you're given to make something strong!
Never introduce variance for the sake of variance - always be careful, purposeful and restrained when introducing RNG
Excessive RNG is widely disliked, as it frequently removes the outcome of a battle from both players' hands and de-emphasizes skill. Whether you're using or facing an RNG-reliant strategy, you need luck to be on your side - and it's easy for a situation to spiral out of control without either player having or getting to make smart choices because it wasn't.
There
are cases when RNG can be used effectively - it's not always a strictly bad thing! But it's important to think about the role that kind of risk serves in battles, when it's worth the trouble and when it's more trouble than it's worth... and it's (dangerously) common for people to cite Mega Evolutions we already have as precedents to say that RNG is okay in
any situation, when there's really quite a lot more nuance than that.
Something that's sort of obvious but very important to note: an RNG-based effect is more likely to happen the more tries you get. That means
RNG favors Pokémon that can try more often.
Bulky Pokémon that can afford to take a lot of hits are way, way better at using RNG than fast, frail Pokémon, because they can afford the bad rolls and have plenty of opportunities to get the ones they want.
Let's use Scald as an example of this. Scald is a move that has a 30% chance to cause a burn, and it's used primarily by Water-type walls. This adds a
major element of risk that their opponents will have to bear in mind - for every turn that a physical attacker is up against a Water-type, it has a serious chance of being crippled in a big way, maybe even for the rest of the match. That means it's not safe to switch a physical attacker in on a Water-type, even if you know it won't do a lot of damage - and it's
definitely not safe to try to
set up on a Water-type, which is a big reason why other passive Pokémon are riskier to use.
This is technically up to luck, but it's a threat that takes skill to plan around. The more opportunities you have to use Scald, the more likely you are to land a burn - at the move's 30% chance, the odds are about 50/50 in just two tries and increasingly in the Scald user's favor past that, so it's basically an inevitability. The counterplay isn't "hope it doesn't happen" - there are ways not to take chances, like using a Pokémon that can't be burned or doesn't mind being burned, or using a Pokémon that can come in safely and deal with the Scald user efficiently without giving them chances to use Scald.
This case study is super relevant here - there's a
reason Scald caught on where Lava Plume didn't, and it's not just because hot water is neat flavor! Water as a type is more conducive to defensive roles than Fire, and it's way more valuable for bulky Water-types to be able to cripple physical attackers and make it dangerous to switch in on them or use them on setup bait than it is for the average Flamethrower-flinging sweeper. On top of that, Fire-type Pokémon are immune to being burned, and it's just as important to bear in mind that they're resistant to Lava Plume but weak to Scald.
The combination of these factors is what makes burns so much more valuable to defensive Water-types than to offensive Fire-types - people occasionally fuss about how much it bothers them that Water-types have the better burning move than Fire-types, but
they deserve it! Burn as a status was designed in a way that Water-types are optimized to use and most Fire-types really aren't
(actually, I find that Fire-types often value spreading bad poison if anything), and the nerf to the status in Generation VII makes that truer than ever.
At its best, RNG is used to
create a threat like this - something that will happen reliably enough that it forces players to plan around it rather than hoping for the best, on a Pokémon that's optimized to have plenty of chances to try,
not something rare enough that it often doesn't happen at all in a battle or something that's equally debilitating pretty much no matter how you play around it (like messing with accuracy and evasion or freezing).
Incidentally, as a rule of thumb:
never balance RNG by making the odds lower - only by making the effect less debilitating.
I would recommend hovering around a 30% chance or even higher - if 30% feels like too much for whatever you have in mind, it's the
effect, not the chance, that's the problem.
Something that almost never happens but is crazy-frustrating when it does (like a 10% chance to cause freeze or sleep) is
worse design than something that happens more often and is less extreme or more counterable (like a 30% chance to cause a burn, which happens often but matters more to some Pokémon than others).
It's also quite player-friendly and easy to think in terms of a 30% chance. A 30% chance to activate on one try is a 51% chance to happen over two attempts (like I said, almost exactly 50/50), and from that point on, it's in the favor of the one using it. It's one of the more clear-cut cases in which RNG rewards Pokémon that can create opportunities for themselves over Pokémon that get lucky.
Of course, you can also avoid the issue entirely by including a non-RNG-based condition instead - even for effects that are "traditionally" tied to RNG. Our recent
Mega Cacturne's Ability, Coup de Grass, is directly inspired by the Quick Claw and very similar to the Ability Quick Draw - when it does activate, it has exactly the same effect as both! - but instead of activating 20% of the time like the former or 30% like the latter, it activates
consistently under specific circumstances (when the target of its move is low on HP).
When
Mega Mismagius was submitted, I gave similar advice to
ausma, the one who created it - its effect originally activated at random (I think 50% of the time?) when using a Poison-type move, but I suggested making it happen only when the target was poisoned instead, and she accepted that.
This is something that I feel contributes to Mega Mismagius's competitive design - even though the effects of its Ability are random, the conditions under which they activate are consistent and preventable and require setup on the player's part. You can keep Alchemist from activating by using a Pokémon that isn't poisoned or one that can't be poisoned, and whether it activates or not, the Ability consistently works to same end of encouraging already-poisoned Pokémon to switch out and endangering only those that choose to stay in after being poisoned. Nearly all of the Ability's effects wear off when switching out, and the few that don't also get rid of the poison status in exchange for something else, preventing any more RNG from taking place; even with the wide variety of potential outcomes and the jokey "embrace the chaos" nature of the Ability, there is a clear way out for the other player and it generally doesn't matter which outcome is rolled.
It's characteristics like this that make Mismagius an effective example of RNG done
extremely well in a way that is harmless to the competitive integrity of the game.
The same cannot be said for many submissions that are vetoed for excessive and unnecessary RNG, so I think it's valuable to talk about why Mismagius is so popular and why many attempts to follow its example have not lived up.
(That said, it's equally important to bear in mind that Mismagius was... sort of a one-off? It was holiday-themed for a special event slate, mostly a joke submission, and in multiple ways designed to be suboptimal and unlikely as a serious contender in high-level competitive play. It's not
meant to be replicated often, and those of us who were part of the community at the time broadly agreed that it was better as a fun special case.
Following Mega Mismagius's example exactly in terms of having a goofy Ability with an unrealistically wide array of special effects is
not actually something we encourage.)
And finally...
Something the fantastic
inkbug says often:
when the best submission wins, everyone wins!
Megas for All is a
collaboration, not a competition! Our goal here is and always has been to make a metagame together - and to make it as enjoyable as possible to play.
It's disheartening when people feel the need to
prioritize winning for themselves or just "putting their name down" over supporting other ideas that they like and showing their appreciation for other people's ideas.
On that note, I would like to take this moment to
encourage collaboration - in cases when your idea is particularly similar to someone else's, please be open to pitching it as advice to them and asking how they feel about incorporating it into their own, instead of making a separate submission with a significant amount of overlap. This arguably hurts both of your chances and makes both of you look worse, and it's been made clear in the past that it can feel
really bad for the person who thinks their idea was taken from them or that they're being robbed of a win.
Of course, not everyone reads other people's submissions
(although I actually really encourage that, if not for this reason!) - this often happens completely unintentionally for ideas that seemingly just make sense! I know the people here wouldn't intentionally take ideas from one another, haha. That said, if I do notice similar submissions that feel like they have a great deal of overlap, please be aware that I may invite both submitters to collaborate on one rather than having both separately, and please try to understand and cooperate if I do.
Mega Zoroark @ Zoroarkite
Mega Alolan Ninetales @Ninetalite A
Mega Delphox @ Delphoxite
Mega Noivern 
Mega Bastiodon's Settle and 
Mega Samurott's Heavenly Techniques. Settle grants Mega Bastiodon enormous power on its special attacks, but only if they haven't been used recently, heavily rewarding the player for making hard reads. Heavenly Techniques has a wide variety of effects depending on how much health Mega Samurott has remaining, putting heavy emphasis on HP management and creating a playstyle that takes great skill to use effectively, just as a samurai shows great skill with its blade.
Mega Inteleon and 
Mega Leavanny were both designed around Abilities that already existed in canon and were designed to use them in ways that other Pokémon didn't.
Mega Reuniclus's Superpower, Hammer Arm and Drain Punch, or a move that it doesn't have yet but contributes directly to its role in a fitting way, like 
Mega Lycanroc's Extreme Speed or 
Mega Clefable's Hex.
Mega Raichu's unique combination of Electric/Fighting 
Mega Dragalge's Acidic Terrain, 
Mega Flygon's Desert Gales, and, most recently, 
), but either the details aren't ironed out completely or not everyone in the council has had time to weigh in, so they're not ready to be polled this very minute! You can expect a followup poll pretty soon with, hopefully, all four of those. C:
Mega Thievul is one of our oldest Mega Evolutions, but it's never really found success in the metagame; although Dark Aura gives its STAB moves an impressive damage output for a Nasty Plot sweeper, it struggles to complement its STABs with coverage and can be stopped in its tracks by something that doesn't mind Dark-type moves.
. Its ability makes it a very threatening wall breaker with good speed and high special attack. It TONKS on the special side, but its weak to physical attacks. This makes it very susceptible to scarfers and faster pokemon in general. Overall, I think mega delphox will find its niche as a solid special wall breaker that doesn't give a crap about pex or something else I forgot after I accidently deleted it lol.
Mega Dugtrio 
Mega Wishiwashi 
and 
Mega Falinks!