At the start of each player turn, the player whose turn it is can choose one of their characters within 6" of the Nehekharan Sphynx to challenge the spirit to a riddling contest. The challenger must take an Initiative test. If the test is failed, the Sphynx devours part of the challenger's soul and the model suffers a wound, with no armour saves allowed. If the test is passed, the challenger receives one of the following special rules, determined randomly, for the rest of the game: Devastating Charge, Heroic Killing Blow or Loremaster (Death) - this last one has no benefit to non-Wizards (i.e. only Wizards can actually use the spells!) but that doesn't stop the Sphynx bestowing it inappropriately.