Explosion Metagross (aka Pick Something To Die)
Metagross @
Normal Gem
Ability: Clear Body
EVs: 112 HP / 252 Atk / 144 Spe
Adamant Nature
- Iron Head
- Stomping Tantrum
-
Explosion
- Protect
As I said in the title, as long as you are careful around Protect, this set will almost always be able to claim a KO on something: your opponent can only choose what. Here's the sort of thing you can do:
252+ Atk Normal Gem Metagross Explosion vs 0 HP / 0 Def Urshifu-Rapid-Strike: 299-352 (87.6 - 103.2%) - 25% chance to OHKO
252+ Atk Normal Gem Metagross Explosion vs 248 HP / 36 Def Rillaboom: 314-370 (77.9 - 91.8%) - guaranteed 2HKO after Grassy Terrain recovery
252+ Atk Normal Gem Metagross Explosion vs 0 HP / 0 Def Zeraora: 379-447 (119.5 - 141%) - guaranteed OHKO
Even Porygon2 is taking 57% minimum from it. I think you get the idea though: it isn't literally OHKOing everything, but it does put most bulkier neutral stuff into KO range of anything, and Iron Head into Explosion KOes a lot of stuff as well. The EV spread is probably customisable depending on team composition, but this is just max attack, enough speed to outspeed Zeraora in Tailwind, and the rest in HP for some extra bulk. Iron Head and Stomping Tantrum not only provide fantastic two-move coverage, but they also are good at threatening Rock- and Steel-types that would usually try to sponge Explosion. Ideally, the set is used with something great at pressuring Steel-types like Heatran or Volcanion, so that the opponent is further limited in Explosion switch-ins.