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Awesome set, but I was wondering if iron ball would be a legitimate choice for the item? Even with no speed ivs, and a speed lowering nature, victini's still pretty fast.
Escavalier, while indeed hard hitting, struggles to get past any steel in the game, let alone a defensive steel. Gliscor and Dragonite often reduce him to set-up bait, to name two prominent non-steel pokemon. In addition, his STABs are resisted by fire types, giving chandy and darm easy...
The problem with Volbeat is that it has no way to deal with Phazers. Like, at all. It's relative lack of speed also means that it frequently gets KOd before able to pull off a pass. Any decent opponent is going to switch out after being encored, leaving Volbeat either at plus 3 but unable to...
Sure it'll 2HKO, but Slowbro will just switch out to a resist(regenerator ftw), to force a switch.
Sub/swords dance/rock gem does indeed own slowbro, but only if scald doesn't burn.