When carried in the inventory, if the player kills a monster that drops bones, the bonecrusher will automatically crush them, granting the player the same Prayer XP that you would receive for using them on an altar. The Bonecrusher is an essential item for any account with longterm goals. It is very useful when killing Dagannoth Kings, Frost Dragons, or any other type of Dragon.
The Bonecrusher can be bought for 2,000 Slayer Points at any of the Slayer Masters. Unlike OSRS, the Bonecrusher has unlimited charges. The Bonecrusher will return to the Refund Box on death for regular players, and normal Ironmen. It will however, completely disappear on death for Ultimate Ironmen.