Old School RuneScape Wiki

Crumble Undead is a spell that requires a magic level of 39 to cast and costs 2 air runes, 2 earth runes and 1 chaos rune. It has a max hit of 16. This spell can only be cast on undead enemies, such as skeletons, zombies, ghost and shades. Crumble Undead is a good way to train magic, as it costs fewer runes than Earth Bolt (same if you are wielding a staff of earth) and hits as hard as Earth Blast. However, this spell cannot be autocasted except with a Slayer Staff, Staff of the dead, Staff of light or Void knight mace.

It is highly recommended against Vorkath, as the spell instantly kills the Zombified Spawn it summons during the fight.

It is also the best method for easily killing the tree spirit in the Lost City quest from a safe spot.

Trying to attack a non-undead NPC with Crumble Undead says "This spell only affects skeletons, zombies, ghosts and shades".


Spell cost
2Earth rune.png2Air rune.png1Chaos rune.png107
Combo runes
1Chaos rune.png2Dust rune.png97
2Air rune.png1Chaos rune.png2Mud rune.png585
2Air rune.png1Chaos rune.png2Lava rune.png107
2Earth rune.png1Chaos rune.png2Smoke rune.png239
2Earth rune.png1Chaos rune.png2Mist rune.png421
2Earth rune.png1Chaos rune.pngStaff of air.png97
2Air rune.png1Chaos rune.pngStaff of earth.png99
2Earth rune.png1Chaos rune.pngMist battlestaff.png97
1Chaos rune.pngDust battlestaff.png89
2Air rune.png1Chaos rune.pngMud battlestaff.png99
2Air rune.png1Chaos rune.pngLava battlestaff.png99
2Earth rune.png1Chaos rune.pngSmoke battlestaff.png97