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 rune2Air rune1Chaos rune81
Combo runes
1Chaos rune2Dust rune71
2Air rune1Chaos rune2Mud rune615
2Air rune1Chaos rune2Lava rune81
2Earth rune1Chaos rune2Smoke rune211
2Earth rune1Chaos rune2Mist rune271
2Earth rune1Chaos runeStaff of air71
2Air rune1Chaos runeStaff of earth73
2Earth rune1Chaos runeMist battlestaff71
1Chaos runeDust battlestaff63
2Air rune1Chaos runeMud battlestaff73
2Air rune1Chaos runeLava battlestaff73
2Earth rune1Chaos runeSmoke battlestaff71

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