Mega Manectric

Mega Manectric is the highest DPS Electric Type Mega Evolution in the game, sporting an impressive Attack and good moveset that lets it fry anything that's unfortunate enough to be the target of its storm-bringing rage. However, it's not the "absolute best" Pokemon in this role. Mega Ampharos has lower DPS, but higher bulk and a potentially useful sub-typing, meaning the choice between these two is very much of kin to the old "Electivire Vs. Raikou" debate. Either way, If you value DPS above all else in your Mega Evolutions, then Mega Manectric is definitely your Pokemon.

Best PvE Offensive Moveset

• Thunder Fang and Wild Charge are the moves to obtain maximum power with Mega Manectric.
• Charge Beam is a step down.
• Thunder is a decidedly weaker choice.
• Snarl, Overheat, and Flame Burst should be TMed, as they don't benefit from Mega Manectric's Mega STAB boost.

• Psychic Fangs is for PvP only. 

• Return is sub-optimal on all fronts.