The Marshmallow of Toxic Loserdom is a toxic, glowing marshmallow handed out by Chris in Campfire Ceremonies to the eliminated campers in Total Drama: Revenge of the Island. At the Campfire Ceremony, Chris will typically hand out marshmallows to everyone present minus the eliminated contestant. The contestant who does not receive a regular marshmallow will receive a toxic one, and must then take the Hurl of Shame.
Chef Hatchet is first seen holding the marshmallow towards the end of the opening sequence. Mike and Zoey retreat from the marshmallow while the other campers look on worriedly. In Bigger! Badder! Brutal-er!, Staci is the first contestant to receive the Marshmallow of Toxic Loserdom. Upon receiving it, her hair falls out.
Dakota does not receive the Marshmallow of Toxic Loserdom at her elimination in Truth or Laser Shark; when Chris tries to give it to her, she runs away. B, Dawn, Brick, and Jo all avoid touching the marshmallow at their eliminations, and it does no visible damage to Mike as it was simply shown in his face before he's put into the Hurl of Shame. In Runaway Model, Sam is hit in the face with the marshmallow and feels pain from it. In Eat, Puke and Be Wary, Scott panics when the Marshmallow of Toxic Loserdom lands on his lap and burns him.
In The Enchanted Franken-Forest, Chef reveals where he gets the Marshmallows of Toxic Loserdom: from a toxic sinkhole in the Mutant Forest of Terror. When Zoey is eliminated by Lightning at the campfire ceremony later that episode, Chef forgets to give her a Marshmallow of Toxic Loserdom and throws it into the bonfire pit, causing an explosion. Cameron uses the Marshmallow of Toxic Loserdom in the following episode to power his computer. It is also drawn on a board to determine if his battle suit for the final challenge will work.
- Sam, Scott, and Staci are the only second generation cast members who touch the Marshmallow of Toxic Loserdom. Other than the pain, it has no physical effect on Sam and Scott; Staci, however, loses all her hair because of it.
- Anne Maria, Cameron, Lightning, and Zoey are the only Total Drama: Revenge of the Island contestants to never receive a Marshmallow of Toxic Loserdom.
- In Grand Chef Auto, Chris refers to the marshmallow as the Toxic Marshmallow of Loserdom.