Rack'n'Ruin are (is?) two Transformers who were surgically combined in a desperate attempt to save their lives. Previously they turned into jets, but now they don't.
Marvel Comics UK continuity
Rack n' Ruin were wreckers. Rack n' Ruin shot a hole in Galvatron. Galvatron got payback. Bye Bye Rack! Bye Bye Ruin!
In his/their first appearence during Target 2006 he is refered to as "Rack and Ruin" but subsequeny appearences pep this up to Rack'n'Ruin.