Helltrapper is a legendary hand crossbow for the Demon Hunter in Diablo III. It requires character level 12 to drop, and can only be found in Act V or Act IV Horadric Caches. The special affix gives a chance on hit (not on attack) to create one free, cooldown-independent Sentry, Spike Trap or Caltrops, Sentries and Caltrops summoned at the Demon Hunter's location, and Spike Traps at the location of the victim. These share the total limit with the normal counterparts, if you have any, and benefit from runes and enhancements. The chance depends on Proc Coefficient, and only triggers off damaging attacks.