Grease pits

Grease pits are a type of arena found on various planets, such as Cybertron and Rigel 6. The grease pits on Rigel 6 host turboworm wrestling matches. While this already sounds like a questionable kind of entertainment, it's still not as bad as what goes down at the grease pits on Cybertron. Located in Polyhex and thus hosted by the Decepticons, the grease pits are among the most brutal and gruesome enterprises in the planet's history. They are not the only type of arena found in Polyhex, and what sets them apart is that in the grease pits, it's Autobot captive against Autobot captive until one of them permanently stops fighting.