The Monstrous cave crawler is an especially strong Cave crawler. The Monstrous cave crawler can only be fought once, during the Desert Slayer Dungeon miniquest, after Smoking Kills. The Monstrous cave crawler awards 1,000 slayer experience when killed. Killing this boss while having the regular version assigned as a task does give more slayer experience. If the player's current task is cave crawlers, then the 15% combat bonus of the (Full) Slayer helmet, Black mask, Hexcrest and Focus sight is in effect, as well as the Monstrous cave crawler counting toward the task.