Dragon Dance Sweeper set(Gen 9)
Ancalagon the Black(Kyurem-Black)@ Life Orb\ Power Herb\ Muscle Band
EVs: 252 Atk, 126 Def, 130 Spe
Ability: Teravolt
Any Speed-Boosting Nature, besides Timid
Tera Type: Ice\Steel
-Freeze Shock\Ice Fang
-Fusion Bolt\Zen Headbutt\Body Press\Iron Head
-Dragon Dance
-Snowscape
Here's how this set is going to work, all of you. Snowscape is for setup, boosting your Defense and increasing the power of Body Press. Dragon Dance is to boost Attack and Speed, the two stats you need for this to work. Freeze Shock does high damage and goes well with max Attack+STAB and Power Herb, but if you aren't using Power Herb, Ice Fang is a good second option(Both of these hit Dragon types hard. Note that I'm not putting down Icicle Spear since there's the risk of only hitting once and dealing barely any damage, so if you use it, equip Loaded Dice to this set). Fusion Bolt is for any Reshiram\White Kyurem that tries to hit you with a Fusion Flare and forgets that Kyurem doesn't take supereffective damage from Fire Types. Body Press\Iron Head\Zen Headbutt are coverage, for each of it's weaknesses, so it doesn't get walled\nuked(Body Press for Rock\Steel Types, being boosted by Snowscape, Zen Headbutt for Fighting Types, Iron Head for Fairy Types, boosted by Steel Tera Type). Tera Ice is for boosting whatever Ice move you choose, While Tera Steel is for turning most of your weaknesses into resistances, and boosting Iron Head. While this guy doesn't breathe fire, like the real Ancalagon did, he'll leave entire teams reduced to rubble by the time he's done!
Statistics:
252+ Atk Muscle Band Teravolt Tera Steel Kyurem-Black Iron Head vs. 252 HP / 252 Def Calyrex-Ice: 230-272 (56.9 - 67.3%) -- guaranteed 2HKO
252+ Atk Muscle Band Teravolt Kyurem-Black Freeze Shock vs. 252 HP / 252 Def Koraidon: 486-572 (120.2 - 141.5%) -- guaranteed OHKO
(Representing likely Reshiram stat spread, and the +2 is the boost that Fusion Bolt gets from Fusion Flare)
+2 252+ Atk Choice Band Teravolt Kyurem-Black Fusion Bolt vs. 0 HP / 0 Def Reshiram: 219-258 (64.2 - 75.6%) -- guaranteed 2HKO
52+ Atk Choice Band Teravolt Kyurem-Black Iron Head vs. 252 HP / 252 Def Tera Fairy Enamorus-Therian: 260-308 (73.8 - 87.5%) -- guaranteed 2HKO
252+ Atk Choice Band Teravolt Kyurem-Black Freeze Shock vs. 252 HP / 252 Def Tera Flying Enamorus-Therian: 680-804 (193.1 - 228.4%) -- guaranteed OHKO