Kyurem-Black @ Lum Berry
Ability: Teravolt
EVs: 56 HP / 176 Atk / 112 Def / 164 Spe
Jolly Nature
- Roost
- Dragon Dance
- Substitute
- Icicle Crash
Role: Physical Sweeper
What It Does: Sets up on certain walls and sweeps. Generally, if its hard counters are gone and this thing gets behind a Substitute, it's pretty much game over. As such this is better reserved for mid to late game sweeps. The EVs are specialized for a reason to make this easier:
56 HP gives you a Stealth Rock number and ensures Seismic Toss won't break your subs. 112 Def ensures a few things. 1) Adamant Non-Life Orb Diggersby cannot break your sub with Fake Out. 2) Unaware 4 Atk Quagsire cannot break your sub with Earthquake. 164 Spe and Jolly means you outspeed max Speed Mega Aerodactyl after a Dragon Dance. The rest goes into Attack.
The main draw here is setting up on Quagsire, usually the go-to dedicated physical wall for setup. If the opponent forgets about Teravolt, all the better. Generally, they'll try to Toxic stall you out, which is why Substitute is so important and the Defensive spread allows you to keep it intact as you Dragon Dance/Roost. So why a Lum Berry if you have Substitute? Because this allows you to switch
into Quagsire as well and not care about Scald or Toxic. It also allows you to get up a Substitute after Sableye has tried to Dark Void or Will-O-Wisp you should you find yourself trying to setup on that. Sub
won't block Taunt or Parting Shot (sound-based), however, so remember that versus Sableye.
Good Teammates: Spinners and Defoggers are important so Kyurem-B can save as much HP as possible when switching in. Even though this set is designed with Stealth Rock in mind, the 1/4 loss is annoying when you also lose another 1/4 to Substitute, meaning a Roost will have to happen sooner rather than later.
What Counters It: There's no guarantee to 2HKO Heatran at +6 and even if
Heatran has no defensive investment whatsoever. I can't stress this enough: remove Heatran first! (+6 176 Atk Teravolt Kyurem-B Icicle Crash vs. 0 HP / 0 Def Heatran: 154-181 (47.6 - 56%) -- 84% chance to 2HKO.) Heatran can do a number of things, including Roar, Taunt, Doom Desire, and Searing Shot (basically a standard set), which will halt your sweep.
Other reliable counters include Scizor, Magnezone, and Aegislash who resist Ice and have Steel STAB.
Notable checks: Chansey is 2HKO'd if she switches into +1 Icicle Crash, but she can get in on a Sub or Dragon Dance and then Whirlwind you out. Ferrothorn can also be 2HKO'd, though not reliably even at +1, and will Gyro Ball you to death. Clefable can force you out before a Dragon Dance with Moonblast. Mega Tyranitar is bulky enough to stomach at least one Icicle Crash at +1, but it needs to come in on the turn Kyurem-B Substitutes or it will lose. Azumarill can stand up to Kyurem-B and break you down with Play Rough. Skarmory Whirlwinds no problem. The main problem with these checks is a flinch from Icicle Crash will ruin them, so count on them at your own risk.
Any Additional Info: I've seen other attacks besides Icicle Crash used, like Ice Punch and Icicle Spear, probably because the accuracy of Crash turns some people off. However, you need the power of a +1 Crash to ensure 2HKO's on certain checks unless you can guarantee their removal before you setup. This requires more team support, which should be at the forefront of your mind when designing your Kyurem-B build.
Leftovers can go over Lum, but then you lose the utility of coming in on Quagsire. A lucky Burn or stray Toxic will halt your sweep before it even starts.
If you're really confident about removing hazards, you could swap out Roost for Earth Power or another physical attack like Fusion Bolt. I find the recovery that Roost provides more important however, in case you're forced into Kyurem-B early and need to patch up Stealth Rock damage or if you start to Sub and realize the opponent still has a way to counter you (Azumarill is bulky Huge Power instead Thick Fat support).
Lastly, here's a list of abilities it ignores with Teravolt that are relevant to STABmons: Unaware (Quagsire/Clefable), Sturdy (Skarmory), Thick Fat (Azumarill/Mega Venusaur).