Elfangor

Elfangor is an Andalite from the Animorphs continuity.

You can't see me!

_{This character has no official visual representation in any Transformers product or media... yet, at least.}

Prince Elfangor is an Andalite prince who sacrificed himself giving the Animorphs their morphing powers, in order to provide them with a sliver of hope against their encroaching enemies, the Yeerks, led by Visser Three. His younger brother, who joined the Animorphs, is Aximili-Esgarrouth-Isthill.