Hello everyone, I'm here to bring you a guide explaining the thought process and essentials behind many balanced and bulky offensive teams. Shoutouts to my tutee,
Algeria, for inspiring me to make this post.
This is in no particular order of priority or anything,
just in the order I thought of things.
Ash-Greninja counter play
Ash-Greninja counter play is one of the most important things for any team; if your team is weak to Ash-Greninja, you should rebuild it. Although "consistent" counter play is hard to come by when factoring in Dark Pulse flinches, Spikes, and what not, it's definitely a manageable threat. The most common way that I see and use myself is by using Pokemon like Toxapex, Tangrowth, Ferrothorn, and Amoonguss to scout for Hydro Pump and then have a Dark-resistant Pokemon like Magearna or Clefable in the back to switch in if Ash-Greninja locks itself into Dark Pulse. Toxapex, Tangrowth, and Amoonguss are particularly notable because they go practically unpunished (if Spikes isn't up) thanks to Regenerator. There's also Tapu Fini and Tapu Bulu, which can neutralize Ash-Greninja for a large part of a match thanks to their amazing bulk and resistances. Additionally, Tapu Fini can remove Spikes, which Ash-Greninja will often try to set up against these type of teams to make progress.
Heatran counter play
Heatran checks are absolutely mandatory. It's very common because it provides a lot for teams and you will often need more than one check to it because it has quite a few ways around its checks and counters with its many available options. Because of its lacking Speed, offensive pressure can often be enough with an offensive check or two like Garchomp and Mega Alakazam in the back, but generally speaking, I wouldn't advice this because it tends to be very unreliable. There's a lot of cool options to check Heatran, like Rotom-W, Tapu Fini, Mega Latias, and Mega Tyranitar. All these Pokemon can check the most common sets, but can lose to others with moves like Toxic, Grassium Z, and Steelium Z. Do note that Steelium Z variants have fallen off the face of the earth, so I often don't find myself worrying about it.
Magearna counter play
You will often need multiple checks to Magearna because of its sheer diversity making it hard to check initially. Mega Venusaur, Heart Swap Magearna, specially defensive Jirachi, and specially defensive Heatran are some good catch alls against Magearna from a defensive standpoint. If you're using a decently fast team, you should definitely note that it can be hard for the Magearna user to set up a Shift Gear initially, because Magearna can often crumble to the offensive pressure that a team exerts. Additionally, Assault Vest sets are quickly worn down, which can be exploited with Pokemon like Mega Alakazam and Choice Specs Tapu Lele. Also note that bulkier Choice Scarf Jirachi variants are often great tools for faster paced teams to deal with Magearna.
Ground-type checks
Having a Pokemon that is immune to Ground is almost universally considered to be mandatory to be able to keep Ground-types like Landorus-T, Garchomp, and Gliscor in check. Some useful Pokemon that often tend to fit these type of teams that are immune to Ground are Tornadus-T, Rotom-W, Zapdos, and Mega Latias, but you should definitely be wary of Supersonic Skystrike Landorus-T with Tornadus-T and Continental Crush variants of Landorus-T and Garchomp with these Pokemon in general. Other Pokemon like Tangrowth and Tapu Bulu can also suffice in this role, though they will need more support than the aforementioned Pokemon, because they're quickly overwhelmed by Z-Moves. Also, note that Landorus-T and Garchomp are particularly easy to wear down, so having faster offensive Pokemon like Mega Alakazam and Greninja to pressure them is often great and will always prove to be useful in practice when combined with one or more of these Pokemon.
Bulky Steel-types
Steel-types are absolutely mandatory on any team to keep offensive Psychic- and Fairy-types like Tapu Lele, Mega Alakazam, and Magearna in check consistently. Individually, they can also provide a lot of other utility. Magearna can provide a stallbreaker, slow pivot, and a resistance to Dark. Celesteela can harass the opposition with Leech Seed and also provides a decent check to Pokemon like Garchomp and Tapu Bulu. Heatran is a really potent stallbreaker, a nice check to other bulky Steel-types, and provides Stealth Rock. Ferrothorn provides an additional resistance to Electric, allowing it to check Tapu Koko, as well as a resistance to Water to scout out Ash-Greninja and Spikes. Mega Scizor is a pretty threatening sweeper in general and is really self sufficient by being able to wear down its own checks and counters with Knock Off over time. Additionally, it can provide Pursuit and Defog support if desired. Lastly, there's Jirachi, which is a provides Wish, Healing Wish, and can also fit on faster paced teams. Neither Heatran nor Ferrothorn are particularly great ways of dealing with Psychic-types defensively, so you will often need another bulky Steel-type with them.
Flying-resistant Pokemon
Flying-resistant Pokemon are incredibly important because Tornadus-T is one of the most common Pokemon in the metagame and will otherwise quickly overwhelm teams. Oftentimes, Pokemon like Celesteela and Leftovers Heatran will not cut it as Flying-type resists in the long run against Tornadus-T, because they will quickly crumble once their item is removed by Knock Off. Additionally, Heatran can be lured with All-Out Pummeling. Pokemon like Rotom-W, Zapdos, Mega Tyranitar, and bulkier Pain Split variants of Magearna are better fit for this job. This is also useful against Supersonic Skystrike Landorus-T, but I covered this already so I won't go any more in-depth.
Tapu Koko counter play
For Tapu Koko, having a combination of a Grass-type and Ground-type is something I'd really advice. Being able to take Tapu Koko's Volt Switch and Hidden Power Ice without being punished hard is why Grass-types are very useful, combine this with a Ground-type like Landorus-T or Garchomp, and you will often be able to force Tapu Koko into awkward positions. Don't assume that it is Choice Specs, though. A bulky Grass-type on its own can be fine against Tapu Koko too, but you will have to accept that you will almost never get a positive momentum trade against Tapu Koko because of it.
Protean Greninja "checks"
To keep Protean Greninja in check you will really have to familiarize yourself with its common sets because, frankly, it can pull off anything if desired by its team, so be very analytical about its set at Team Preview. Generally speaking Toxapex and Ferrothorn are pretty good blanket checks to scout its set, but even they can't go unpunished against sets with Groundium Z, Fightinium Z, Extrasensory, and Hidden Power Fire respectively. I'd definitely advice having faster Pokemon like Mega Alakazam and Choice Scarf Landorus-T in the back to pressure it out, minimizing its overall impact. You will often have to make aggressive doubles against Protean Greninja with Pokemon like Mega Alakazam and Landorus-T, though, which is really risky.
Toxapex checks
Having a consistent way of dealing with Toxapex is absolutely mandatory, no team can get away without it. You can do this through various ways that are all able to provide different kinds of utility on top of this, like Psychic-types (not Stored Power Mega Latias), Roost Tapu Koko, Taunt Tornadus-T (should never be your only check), and Gliscor, for example. A common misconception that I see among newer players is that Toxapex is a reliable check to Heatran, this is wrong. In reality, Toxapex will often find itself overwhelmed by the combination of Magma Storm, Taunt, and Earth Power.
Mega Mawile counter play
People are often looking for ways to play around Mega Mawile defensively, but this approach just isn't that great. The best way to keep Mega Mawile out is with offensive pressure because its relatively mediocre Speed tier will often leave it in awkward positions against Pokemon like Landorus-T, Tapu Koko, and Magearna. Additionally, its relatively low bulk will quickly let it down. However, having a Pokemon that can pivot into Play Rough is absolutely mandatory, because if Mega Mawile gets a free turn to come in, you have to have a way to prevent it from spamming Play Rough. Some of the most common ways of dealing with this are Heatran, Mega Scizor, and Gliscor, which can switch into an unboosted Play Rough relatively well.
Kartana counterplay
Kartana is a really big deal, because it's very prominent and provides a ton for teams offensively. However, dealing with it is pretty straight forward, all you really need is a way to outspeed its Choice Band and Swords Dance sets and a way to consistently pivot around Choice Scarf variants. Tornadus-T and Mega Alakazam are two particularly great ways of achieving the prior, while Pokemon like Tornadus-T, Zapdos, Mega Scizor, and Amoonguss can pivot around Choice Scarf variants rather handily. Zapdos and Mega Scizor are also particularly great checks to Choice Band sets and can deal with Swords Dance variants, though that is greatly dependant on its Z-Move.
Stallbreakers
I won't go in-depth much, but going in without stallbreakers against a stall team is practically a death sentence. Luckily, many of these Pokemon provide other niches besides breaking stall, so they shouldn't be particularly awkward to fit on teams in general. Many of these stallbreakers can be prepared for by stall, though. This can be seen by the rise of Pokemon like Mega Aggron, Moltres, and Heart Swap Magearna on stall teams, so be wary.
Stealth Rock and Defog are mandatory on practically any team to punish switches and to keep your own team from being too weak to opposing hazards. Spikes and Toxic Spikes, however, are just options that can often provide to be very useful and the Pokemon that can set it are often great natural fits in general.
