When Kappa Attack HM

He's using Arcane Mimicry, which copies the other Elementalist heros elite skill. Thanks Pew.

I feel dumb now

I gotta try Jeydra's team setup...
other guys' posts seem doubtful, since they don't post actual screenies of third cleansing spot win without cons on. Warning: my builds are optimized to caster primaries, melee characters will probably find them subpar @_@

You could try talking to EFGJack or something, no idea if he's done the quest yet, he was talking about using Ebon Escape to teleport between spawns though.

Strangely the second before last wave never gave me problems; I just set up spirits where they're coming and destroy them. You might want to try more hex removal on the UA; the Kappa have a LOT of hexes and much of the pressure comes from stuff like Suffering.