Reminder: The meta is melees doing melee stuff and casters spamming OP spells.
The character skills don't matter in day 3
The ultimates are a crutch in day 3
The only thing that matters as a caster is spamming OP spells.
Revenant is not trash, you pick her if you want to use seals instead of staffs.
Guardian is fine if he maintains aggro but has the lowest DPS in the game and has a poorly implemented kit.