So I've been doing a lot of playing around in Super Singles with this team and I've had a fair amount of success.
Omastar ♂ - Modest @ Focus sash
Ability: Shell Armor
EVs: 252 Sp. Att / 28 Sp. Def / 228 Speed
Surf | Shell Smash
Ice Beam | Ancient Power
Haxorus ♂ - Adamant @ Lum Berry
Ability: Mold Breaker
EVs: 64 HP / 252 Attack / 192 Speed
Outrage | Poison Jab
Earthquake | Dragon Dance
Scizor ♂ - Adamant @ Scizorite
Ability: Technician
EVs: 252 HP / 252 Attack / 4 Speed
Swords Dance | Bullet Punch
Bug Bite | Superpower
This team revolves around Omastar, a fantastic special sweeper. If Omastar dies then Haxorus or Scizor can set up and pick up where he left off. I love the dragon/steel combination in the back since they have good synergy when it comes to type-resistances. They can both take at least one hit to set up and start their own sweep. The idea for this team is that (except Scizor) everyone should be able to outspeed almost all non-scarfed pokemon after a boost. (It's ok if they can't outspeed Accelgor or Electrode. The ability to hit harder is more valuable with the Modest/Adamant natures than losing that to outspeed pokemon who aren't a huge threat to the team.)
Adamant Haxorus (base 147 attack remember) with a STAB Outrage will OHKO most everything (save steels and fairies) after a Dragon Dance. (That's what Earthquake and Poison Jab are for.) Scizor is bulky enough to be able to max out his attack with Swords Dance sometimes, but only one Swords Dance is usually enough.
I was having a lot of fun with this shell smashing Omastar so it got me thinking about other shell smashers I could use. Yes, everyone loves Cloyster, but I wanted a special attacker on my team out of fear of getting walled. Also, I didn't have a Cloyster, but maybe I can try one out now that I want to try a whole bunch of others too.
Omastar:
- After a Shell Smash, outspeeds all non-scarfed pokemon slower than Electrodude.
- Hits everyone for at least neutral damage except for Empoleon and Poliwrath.
- His biggest problem is hitting the pesky water types (who usually have relatively high special defense), so at least with STAB Ancient Power, he's able to hit Lapras, Dewgong, Cloyster, and Walrein. Other water types that he can't take out, Scizor usually cleans up. I ended up going with STAB Ancient Power over non-STAB Earth Power because of the off-chance of raising stats, which is nice earlier on in the battle.
- Surf is a great STAB move and is able to OHKO most everyone that it hits neutrally (after a Shell Smash)
- What is great about leading someone weak to electric is that you tend to not get crippled by thunder wave right off the bat. Electric types appear to generally just go for the KO with Thunderbolt/Thunder instead of doing a Thunder Wave first.
Alright, now I want to compare to other Shell Smashers that I want to try out:
Gorebyss ♀ - Modest @ Focus Sash
Ability: Swift Swim
EVs: 4 HP / 252 Sp. Att / 252 Speed
Shell Smash | Surf
Psychic | Ice Beam
Gorebyss is very similar to Omastar. Similar Speed and Sp. Attack, similar moves, similar type coverage. There are really just two main differences between Gorebyss and Omastar.
1. Type defenses. Adding the rock typing to Omastar does give a resistance to normal, poison, and flying. But they're not all that useful when you consider the trade off: Added a weakness to ground and fighting (two very common types), and lost resistances to water and steel (also pretty common). So I like Gorebyss' defensive typing better.
2. For the last move slot, Omastar has a choice between Ancient Power and Earth Power. Gorebyss has a choice between Psychic and Shadow Ball. Neither set gives perfect type coverage, but I like Psychic on Gorebyss because it's more powerful than shadow ball, plus it does allow her to OHKO Poliwrath.
Cloyster ♂ - Adamant @ Focus Sash
Ability: Skill Link
EVs: 124 HP / 252 Attack / 132 Speed
Shell Smash | Icicle Spear
Dive | Rock Blast
Cloyster -- not sure how well a third physical attacker will fit into my team but we'll go with it. His attack isn't really all that high (which was my initial turnoff to him) but he makes up for it with Skill Link. Guaranteed 5 Icicle spears is like an Ice Punch if Ice Punch had a base power of 125 (just with a little more damage variability). Going with Dive over Razor Shell because it's slightly more powerful and more accurate. (I've found that accuracy is very important in the Battle Maison.) Rock Blast is another great way to make use of skill link and gives Cloyster the same type coverage as Omastar, just with a different typed primary Stab Move (Icicle Spear). I'm not too worried about Rock Blast's less than 100% accuracy because on average it will still hit 4.5 times.
Crustle ♂ - Adamant @ Leichi Berry
Ability: Sturdy
EVs: 4 HP / 252 Attack / 252 Speed
X-Scissor | Rock Slide
Earthquake | Shell Smash
Crustle is fundamentally different than the previous three in that he has Sturdy which means he doesn't need a focus sash. This gives him the opportunity to use another item, and he needs it. His speed is just ok and his attack isn't great, so he's gonna have to make up for it somehow. I'm torn between a Leichi Berry and a Salac Berry for Crustle, but I'm leaning toward Leichi Berry because he is still at least able to outspeed everyone Greninja and slower with full speed EVs, and his attack stat really needs a boost. He's not a water type, meaning he has different type coverage than the others, so it will be interesting to try. His primary STAB move is X-Scissor, and for accuracy reasons, I think that Rock Slide should just be reserved for flying types that resist his other two attacks. He is the only non-water type on this list which means that electric types will try to cripple him with thunder wave instead of attacking for the KO, making it slightly harder for him to set up a shell smash.
Carracosta ♂ - Adamant @ Salac Berry
Ability: Sturdy
EVs: 4 HP / 252 Attack / 252 Speed
Waterfall | Rock Slide
Shell Smash | Earthquake
Carracosta is even slower than Crustle, but at least he has a decent attack stat. Salac berry is definitely the choice here to go with Sturdy. But without access to a decent physical Ice type move, Carracosta will have to make do with Rock Slide for hitting grass types. But at least he's got access to Waterfall and Earthquake as a physical attacker, something that Cloyster can't say he has. Like with Crustle, let's save Rock Slide for the flying types.
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I would also love to try out this Tough Claws Barbaracle, but I think I'll just wait until Sun and Moon come out!
Barbaracle - Adamant @ Focus Sash
Ability: Tough Claws
EVs: 88 HP / 252 Attack / 168 Speed
Shell Smash | Razor Shell
Earthquake | X-Scissor
The only real turnoff here that I can see is Razor Shell's 95% accuracy. He should totally be able to learn waterfall. I went with X-Scissor over Rock Slide to make more use of Tough Claws and its superior accuracy, but I think flying types would be a problem if they resist water.
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You can forget about Shuckle, Macargo, Torkoal, and Huntail. The first three are way to slow even with a Jolly/Timid nature. Huntail may be ok, but he doesn't have much of a moveset for physical attacking, and the pokemon above have all the advantages that Huntail might have, and they do it better.