Most Marathon events are just an excuse to shoot UESC bots. They aren’t complicated. But Tox Clear rooms are the exception that requires you to stop and think for a second. Exploring Tau Ceti IV, you will inevitably come across map icons that mark chambers choked with bright yellow poison. Tox Clear events are a room full of loot, but the air will kill you if you just barge in. To get the gear, you have to neutralize the toxic gas. It’s one of the few spots in the game where pulling your trigger won’t solve the problem. You’ll have to run a quick puzzle under pressure instead of a firefight.
Marathon Tox Clear Events Guide
To stop the gas during a Tox Clear event, you need a Hazard Override Card. It’s a rare Enhanced Key that looks very similar to a Lockbox Key and can be found randomly from room shelves, containers, small lockboxes, dead players, and pretty much anywhere loot drops.
They are not very common, but aren’t impossible to find either. High-tier POIs like North/South Relays on Perimeter, or Complex on Dire Marsh usually spawn them more often. When you have a Hazard Override Card, stash it. You can exfil with it and save it in your inventory so it’s available for a future run instead of hoping to find one mid-match.
Once equipped with a card, follow these steps to complete the event:
- Look around just outside the gas room to find a nearby bright red computer console. The laptop screen will show a symbol that matches the inactive gas extractors in the room.
- Interact with the laptop to insert the Hazard Override Card. The system will take roughly 15 seconds to repair and extract the poison.
- You will have about 30 seconds before the gas floods back in. Most Tox Clear rooms have a handful of trunks — Salvage, Cores, Implants, valuables, occasionally a solid weapon, so you shouldn’t even need the 30 seconds if you loot through fast.
After the gas returns and you want another pass, you’ll need a second Card to run the computer again. Even without it, you can still loot Toxic rooms, though none of them are very safe. Mechanic’s Kit clears the Toxin status effect and gives 30 seconds of immunity. Use one, then enter the gas room, grab what you can, and get out before it wears off.
If you don’t have kits, use a Triage or find someone playing as one. Their healing drone can outpace the gas damage for a while. Toss the drone into the room and stand within its radius to loot. Although you’ll be in a rough condition by the time you come out, you’ll still be alive.
Lastly, you can directly enter the chamber, tank the damage, and collect the items while the gas eats through you. The Toxin debuff doesn’t only chip away at your health; it tanks the Hardware stat, which means any healing you use afterward will barely move the needle. When your health is already low halfway through a run, this is a quick way to die. Still to play this way, make sure to have enough medkits to compensate for the nerf.
