Venomoth can be pretty forgetable, but now that I look at it, it's actually pretty good.
Out of the three, I'd have to say Tinted Lens is the best. Wonder Guard and Shield Dust are only useful in certain scenarios.
Perfectly Ultimate Great Venomoth
Ability: Tinted Lens
Item: Black Sludge/Wise Glasses
Modest/Timid (252 SpA/252 Spd/4 HP)
Wait a sec, did I just use a Yu-Gi-Oh reference? I am such a nerd...
Anyway, a pretty basic set, but pretty effective, too. Quiver Dance is awesome, and is my personal favorite when it comes to stat-up moves. +SpA, +SpD, AND +Spd? Yes please! Bug Buzz is Venomoth's best primary STAB move, and the chance to lower the opponent's SpD is nice when it happens. Toxic+Venoshock is an awesome combo, especially with Quiver Dance and STAB. Wise Glasses boost SpA while Black Sludge heals. Your choice.
Tinted Lens is AMAZING for Venomoth, considering it's lackluster movepool. A whole lot of Pokemon resist both it's STABs, so esentially negating that resistance is pure awesomeness.
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