Sludge was one of the five Dinobots. Jazz found his stasis locked chassis somewhere in an underground Energon pool in the Sea of Rust. He took his memory core in an attempt to find out what happened to the rest of the Dinobots. Considering that the entire area was later flooded with toxic liquid, it is unlikely that Sludge survived.
- Sludge's dinosaur mode was going to be that of a sauropod.
- Sludge is the only Dinobot who cannot be played as in the game.