Turboworm

Turboworms are an alien lifeform in Generation 1

Turboworm wrestling is a particularly macabe form of entertainment native to Rigel 6. For the price of an admission, spectators get a dose of unadulterated carnage serged up courtesy of the Grease-pits.

The term 'Grease-pits' is generally asssociated with mechanoid blood sports, so Turboworms are probably mechanical lifeforms. Alternately, the sport could feature mechanoids wrestling the dangerous Turboworms.

Fiction

Marvel Comics

Prior to the Ark's launch 6 million years ago, Grimlock and Sludge saw Turboworms werestle on Rigel 6. The dim-witted Sludge thought the proceedings quite fun, but Grimlock had a noticably more chill response to the pointless slaughter, merely callign it interesting.

Marvel US #27 Much later on Earth, Sludge was reminded of the Turboworms when he witnessed Trypticon's assault on the disabled Autobot forces. Again, Grimlock was less enthusiatic at the carnage.

Snarl reminded Grimlock about admission fees for Turboworm wrestling, but a later Letters Page indicated only Grimlock and Sludge had been present. Possibly Snarl was just needeling Grimlock.