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 rune80
Combo runes
1Chaos rune2Dust rune70
2Air rune1Chaos rune2Mud rune492
2Air rune1Chaos rune2Lava rune80
2Earth rune1Chaos rune2Smoke rune210
2Earth rune1Chaos rune2Mist rune264
2Earth rune1Chaos runeStaff of air70
2Air rune1Chaos runeStaff of earth72
2Earth rune1Chaos runeMist battlestaff70
1Chaos runeDust battlestaff62
2Air rune1Chaos runeMud battlestaff72
2Air rune1Chaos runeLava battlestaff72
2Earth rune1Chaos runeSmoke battlestaff70

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