The mutant head was a gimmick present on all of the Deluxe class and larger Beast Wars toys from 1996 and their later redecos and retools. A portion of these toys had two heads, one of which was a biological-looking "mutant" head and one of which was the actual robot head of the toy. Other toys utilizing this concept instead had masks which covered the robot face, or heads which could be rotated to show either face. Later Beast Wars toys did not use the mutant head gimmick, perhaps because it was not used in the television show due to budget constraints.
While this concept was barely explored in this continuity's fiction, some characters are more identified by their mutant head than their robot head, such as Waspinator or Tarantulas. In cases of redecos of molds with this feature, the new character will often be identified by the opposite head the original character used in the fiction. This is the case with Buzz Saw and Blackarachnia, who are both identified using robot heads. Also, Tigatron's boxart shows him with his mutant head, though he was never seen in the animated series in this fashion.
Later fictions would sometimes incorporate this gimmick in the portrayals of newer characters based on redecos of the original toys; Barbearian's mutant head is a key point in his split personality, while T-Wrecks is shown to use his mutant head as a battle-mask in "Betrayal".
Notably, in the 2006 retool of the original Ultra class toys for Optimus Primal and Megatron, this feature was removed in favor of more show-accurate head sculpts (then added again for another release using even more show-accurate colors). This feature was also removed in various retools of different toys, such as the Cyborg Beasts and Hardhead.
Toys that possess mutant heads
- Deluxe Rhinox
- Ultra Optimus Primal