Poison Gas can be found killing the zombie variant of Undead ones on Karamja. All players within a square of the gas would receive 2-3 damage per hit. To avoid this, players need to be at least two squares away from the gas.
Historical[edit | edit source]
Poison Gas was also a former random event while Thieving chests. Occasionally, while looting a chest, the chest would become stuck and gas would come out and damage nearby players. Despite the fact it had a green hitsplat, the gas did not inflict poison.