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A player casting crumble undead.
Crumble Undead requires a magic level of 39 and can do a maximum of 15 damage per spell. It can only hit undead monsters, such as Shades, Zombies, Skeletons, Ghosts, low-levelled Revenants, Zogres and Ankous. It does not work on the Barrows brothers, certain high-levelled Revenants, mummies or the undead boss fought in the Shilo Village quest.
In free-to-play, it is a more cost-effective way of battling undead, as it hits as high as Earth blast but costs less than Earth Bolt.
It was once able to be autocast only by using a Slayer staff or a Void Knight mace, but as of the update of 2 September, it is now autocastable with any staff or even without a staff.
Crumble Undead costs 169 coins for each cast, if no staff is used, but an earth staff is recommended in free-to-play. This brings the price down to 109 coins per cast. Members can use dust runes which brings the price down to 137 coins for each cast, also allowing them to use a magic staff that gives a 10% max hit boost.
Remember, you cannot use Ancient Magicks or Lunar Spells if you are using regular Magic.
- At one point, it was an extremely effective way of training magic, but the XP for casting it has since been halved (so only +2XP/hit) and so it is no longer very effective.
- Attempting to cast crumble undead on anything that is not undead will give you the message "This spell only affects skeletons, zombies, ghosts and shades".
- Many players have commented that its appearance is very similar to Wind Wave. Also, when the spell shoots out of the player's hand, it consists of three rotating "mini wind wave"s, but when the spell hits the target, it explodes into four "mini wind wave"s.
- In RuneScape Classic, Crumble undead gave 98 experience per shot.
- Despite Banshees being Undead, Crumble Undead cannot be used against the Banshee Champion underneath the Champion's Guild. As previously stated, it brings up the message, "This spell only affects skeletons, zombies, ghosts and shades".