Staraptor@Air Balloon
Ability: Intimidate
Modest nature
252 SpA/4 SpD/252 Spe
-Aerial Ace
-Hidden Power Fighting
-Hyper Beam
-Growl
This is the best Staraptor set. Staraptor's special movepool is shallow, so we need Hyper Beam, a powerful STAB move, to deal with physical walls. Staraptor gets no Fighting moves other than Close Combat, so HP Fighting gets rid of Steel and Rock types that wall both of its STABs and doesn't drop Staraptor's defenses, which are low. Aerial Ace is a physical ARAB that hits Chansey without losing HP. Growl stacks with Intimidate, because as i mentioned earlier, Staraptor is frail, and we need the opponent to have its attack as low as possible for us to sweep. Air Balloon prevents Gravity working against the Flying-type. Staraptor is already very strong physically, so it doesn't need Attack investment, but it needs Sp. Atk investment since it's so low. Staraptor also doesn't hurt itself that hard if it becomes confused.
