>>42604869I don't think it's anything super special.
Max HP, Max Attack, Adamant
Defiant, still undecided on the item.
Swords Dance/Sucker Punch/Iron Head/Taunt
Assuming the Dragapult has no HP/DEF investment, but perfect IVs in both, Sucker Punch will OHKO 87.5% of the time with no boosts. a Defiant or Swords Dance boost will let it OHKO that often too DynaDrag too. Any sort of damage boosting item guarantees those OHKOs.
The max HP lets it survive Fire Blast 75% of the time assuming the Dragapult has perfect Sp. Attack IVs and 252 EVs, and obviously lets it survive Flamethrower too (assuming no Specs). Physical variants of Dragapult do even worse because they have no Super Effective moves
Taunt is just there because it's helpful in general.
The only Drag I've run into that fucks with it is ones that run Will-o-Wisp.