Prepare for wave 1
Aether carries over from every run. Spend it on powers that last.
Graphics changes apply after a reload.
Goblins, ogres and worse march on the castle. If they break the gate they go for the Heart; if the Heart breaks, the run is over.
Elemental reactions. Spells combine: fire on a frozen foe Shatters it, lightning on a burning foe Overloads in a blast, lightning on a chilled foe Superconducts farther, and frost on a burning foe bursts into stunning Steam.
Boons. After wave 5 and after every boss you choose one of three boons that last the run.
Pop goblin sappers early: their blast hurts their friends. Fire stops trolls from healing.
Choose one. It lasts until the run ends.