>>16596464Well originally, it only had 70 BP, and had that retarded ability to only hit things of the same type, so it wasn't worth it.
This gen it got fuckin' MEGABUFFED and has 120 BP. So now it's more of an amazing move with a shitty drawback, making it very situational.
It would be especially useful on Vaporeon because previously it had jack shit to use against other bulky water types. Synchronoise now is the answer to that, killing basically anything that isn't water-dark type, since it deals Psychic-type damage.
Tentacruel will also cease to ever be a thing, because of that.
Jolteon also benefits from it because of its high Sp. Atk., although it's still very situational. Even moreso than Vaporeon.