Mask of Glee - The RuneScape Wiki

A Mask of Glee is used in puzzles in Sliske's labyrinth, during Sliske's Endgame. They can be taken from shadow casters.

Jas - The RuneScape Wiki

Mask of the Green Wyrm - The RuneScape Wiki

Hallowe'en mask, RuneScape Wiki

Mask of the Abyss, RuneScape Wiki

Mask of the Ganodermic, RuneScape Wiki

Mask of the Abyss, RuneScape Wiki

Mask of Mourning - The RuneScape Wiki

Sliske, RuneScape Wiki

With the new Fire Sale relic announced, this would mean free 99 Construction and Farming all together using the garden store in Falador from 1-99 : r/2007scape

Masori headdress (beta) - OSRS Wiki

Gas mask - The RuneScape Wiki

August 22, 2014 – Why I Game

Mask of the Green Wyrm - The RuneScape Wiki

Black mask, RuneScape Wiki

Blue H'ween Mask Tribe Event! (The Blue Demons)