The black mask is one of the most valuable pieces of Slayer gear in Old School RuneScape. Worn in the head slot, it has the same defensive stats as a black med helm but provides a 16.67% boost to both Attack and Strength against monsters on your current Slayer task. Because of its rarity, many players either grind for it directly or buy one with OSRS GP on the Grand Exchange. To equip the mask, you need 20 Strength, 10 Defence, and 40 Combat level.
How to Get the Black Mask

The black mask is a rare drop from Cave horrors and Cave abominations. Cave horrors require 58 Slayer and the completion of Cabin Fever to access their habitat on Mos Le’Harmless, where they drop the mask at a 1/512 rate. Cave abominations also drop the mask at the same 1/512 rate, but with three independent rolls per kill, making them more efficient for farming compared to Cave horrors.
Since the grind can be lengthy, many players choose to purchase the black mask directly from the Grand Exchange using OSRS Gold.
Special Effects and Charges
When charged, the black mask has a passive effect that can reduce a monster’s Defence by 2 + 7% of its current Defence level. Each activation consumes one of the mask’s ten charges. To trigger, the monster must be within 10 tiles, directly attacking the player, above 50% health, and not already debuffed. The effect has a one in ten chance per hit to attempt activation and rolls against the monster’s Magic defence. Once all charges are consumed, the Defence-reducing effect is lost permanently, though the Slayer damage boost remains.
Imbuing the Black Mask
The black mask can be imbued into the black mask (i), which expands its bonuses to include a 15% Ranged and Magic accuracy and damage boost in addition to its melee benefits. This makes it highly desirable for hybrid combat situations. Players can imbue the mask through different methods:
- Nightmare Zone: 1,250,000 points (or 625,000 with Hard Combat Achievements).
- Soul Wars: 500 Zeal Tokens.
- PvP Arena: Scroll of Imbuing for 200 points.
Imbuing a charged mask carries over its remaining charges, and the imbued version consumes charges in the same way.
Combining into a Slayer Helmet

With 55 Crafting (boostable) and the Malevolent Masquerade unlock from a Slayer Master for 400 Slayer reward points, the black mask can be fused with other Slayer headgear to create a Slayer helmet. This combination retains the Slayer bonuses of the mask while freeing up inventory slots. Keep in mind that fusing the mask into a helmet causes all charges to be lost.
Other Uses
Beyond combat, the black mask has niche utility. Players with 53 Construction can use it to upgrade their Player-Owned House combat dummy into an Undead combat dummy, which interacts with the ancient mace special attack to improve Prayer point restoration.
Final Thoughts
The black mask is a core upgrade for Slayer enthusiasts in OSRS. Whether obtained as a drop from Cave horrors or Cave abominations, or bought directly with OSRS Gold, its damage-boosting potential makes it a priority for mid-level accounts. Its ability to be imbued and eventually combined into a Slayer helmet ensures that the mask remains useful throughout a player’s progression.