Kymbra Chimera

Kymbra Chimeras were a shapeshifting species similar in abilities to the Whifferdill.

Biology
The Doctor described them as a prmitive relative of the Whifferdill. They power their shape changes with stolen energy. They were unable to accurately copy clothing so it appeared fused to the flesh. (DWM: Changes)

History
A Kymbra Chimera was brought onboard his TARDIS by the Doctor as it was disguised as the cute Swuffle. He placed it in a synthetic habitat in the TARDIS zoo. When it escaped, it took on the appearance of the Doctor and then Peri. It battled with the Whifferdill Frobisher, both changing to overpower the other. The chimera was winning when it was sucked out the TARDIS by the Doctor. (DWM: Changes)