BUILD YOUR DECK, OPEN YOUR PACKS Plan before you slaughter, because once the mission starts you fight with what you brought. Before every mission you assemble your loadout from the spells you own, and that loadout is your deck. A deck weighted toward Summoning wins the field by crowding it, with skeletons soaking the horde while you cast. A deck weighted toward Blood Magic hits harder and sacrifices your life to do it.

The points you earn on a run buy booster packs, and every pack adds spells to your collection, so your next deck comes out of a wider pool.

TWIST YOUR SPELLS WITH MUTATIONS Mutations sit on top of the skills you carry and change the way they work. A mutation riding your bone spear sends it out in a pattern you have to learn again, and one on a summon calls up another archetype of undead. Others reshape the ground an area spell covers or give an aura a character of its own, so a spell you have cast a hundred times comes out of your hands changed.

TEN SCHOOLS OF DARK MAGIC Every spell in your collection belongs to one of the ten schools of dark magic. There are 200 spells in all, and every school combines with every other.

31 PLAYABLE HEROES Many heroes are built around two or three schools at once. Ravena Bloodscythe pairs Blood Magic with Harvest, and Seraphon Wraithblade blends Harvest, Death Knight and Soul Magic.