Daemon Vector is set in medieval times where European adventurers recover artifacts from Asia. Now one of these artifacts turns out to bear a curse and transforms all nearby humans into zombies. The player takes the role of a hero to wipe out the zombies.

Daemon Vector is a a classical hack & slash game: The camera is fixed behind the player character which performs hits and combos by using the mouse buttons. Combo attacks can only be used when the player has enough special energy which is earned by performing regular attacks. The basic gameplay structure is that the player has to clear a room of all zombies. Then he receives a key to unlock the next room.

The player can choose between Asgard who fights with swords and Rhea who prefers heavy but slow weapons. The two have different combos and character values, e.g. health or armor. These can be upgraded with experience points which are earned by killing enemies. After every level the player can take one of two pieces of equipment, e.g. a ring or a sword, which give special abilities like poison resistance.