Mutant head
Mutant Heads were a gimmick present on all of the Deluxe class and larger Beast Wars toys from 1996 and their later redecoes 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.
While this concept was never 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.
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. This feature was also removed when Waspinator was retooled into Dirgegun, to facilitate the figure's new weaponry gimmick.
Characters whose toys utilize this feature include:
