Rigor morphis

Rigor morphis is a reflex action performed by dead Transformers, where the corpse shifts to the preferred mode of the individual Transformer. The preferred shape is sometimes their alternate mode.

Fiction

2005 IDW continuity

A NAIL, in protest of the Autobots' "illegal occupation" of Cybertron, kept transforming nonstop, burning out his transformation cog and killing himself. During Ratchet's examination of the body, it underwent rigor morphis and transformed into its alternate mode. How to Say Goodbye and Mean It Thunderclash performed rigor morphis when he was at death's door, locking him in vehicle mode.The Sensuous Frame

Notes

• The term is a take on rigor mortis, the stiffening of the body after death.