Delirium is the rune word 'LemIstIo' for helms in Diablo II: Lord of Destruction. Delirium grants a proc that, when activated, transforms the caster into a level 50 Bone Fetish for roughly 60 seconds. The newly transformed Fetish's normal attack is a headbutt. While Delirium can be made in any type of helm and can be used by any class, it is best used by a Druid since he can transform back from this Fetish form by using the Werewolf or Werebear skills.