A Black mask

A Black mask will boost both Attack and Strength by 15% while fighting monsters that have been assigned by a Slayer Master. They can be obtained by fighting Cave Horrors in a cave on Mos Le'Harmless, or by buying them from other players. When meleeing Cave Horrors, a Witchwood Icon and light source is required. The masks have a number of charges, represented by a number following the item title, (e.g.; black mask(10), black mask(3), ranging from 1-10). When the player still has charges, he or she will sometimes have his or her opponent's Defence decreased. Each time this effect randomly takes place, the player will lose one charge. When Black masks lose all their charges, they have no number. There is no known way to recharge them at this time. Black masks with no charges retain their Attack and Strength boosts. You can now remove charges from a Black mask with an update that came out 2 November 2010.

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