When a character first learns Thaumaturgy, the player selects a path for the character. That path is considered the character's primary path, and she automatically receives one dot in it, as well as one Level One ritual. Thereafter, whenever the character increases her level in thaumaturgy, her score in the primary path increases by one as well. Rituals are learned separately, as part of a story; players need not pay experience points for their characters to learn rituals, though they must find someone to teach the rituals in question.

Each time the character invokes one of the powers of a Thaumaturgical path, the thaumaturge's player must spend a blood point and make a Willpower roll against a difficulty of the power's level +3. Only one success is required to invoke a path's effect - path levels, not successes, govern the power of blood magic. Failure on this roll indicates that the blood magic fails, while a botch signifies that the character loses a permanent Willpower point.