The Green halloween mask is a tradeable cosmetic item. Green halloween masks can be obtained by completing one of the Hallowe'en holiday events that occur once per year. This also rewards the player with all other holiday items associated with Halloween.
After player decided polls, it was decided that all tradeable rares will be distributed during their corresponding holiday events thus making them seasonal rares and not completely rare, this to prevent them from being worth hundreds of millions of coins again, like in RuneScape 3.
All 3 Hallowe'en masks were dropped from 17–24 June 2013 across Gielinor.