A creature with this special quality (usually an undead) is less easily affected by clerics or paladins (see Turn or Rebuke Undead, page 159 of the Player's Handbook). When resolving a turn, rebuke, command, or bolster attempt, add the indicated number to the creature's Hit Dice total. For example, a deathshrieker has 18 Hit Dice and +4 turn resistance. Attempts to turn, rebuke, command, or bolster treat a deathshrieker as though it had 22 Hit Dice, though it is an 18 HD creature for any other purpose. This is an extraordinary ability.