Corruption
Delirium
Necromancy


Spam Lobs of charged Mastery-Attuned Necromancy Attacks
If the Enemies are getting a nuisance use Delirium's Despair (Mastery) ability to control the crowd and let them cower in fear. Or just to teleport into the fray with charged Despair Nova.
Let the charged Corruption Missiles do their job. Once the first enemies fall and your pustulating plaque ridden undead start attacking everyone you can add a pinch Delirium Mirror-Damage at your own discretion.