Jaw Titan (Anime)

The Dancing Titan is the Titan form of Ymir.

Appearance
The Titan is a class Titan with long, black hair, very large irises and an agile, chimpanzee-like body. This form grants Ymir rather long arms and sharp claws. The smallest Titan shifter known yet, this Titan form has a mouth with all pointed teeth, as well as sharp claws that can either be used to grasp on to things or for combat.

Clash of the Titans arc
At some unknown point in time, Ymir gained the power of the Titans. During the Wall Rose invasion, Ymir is among the recruits of the Scout Regiment at Utgard Castle when it is overrun by Titans commanded by the Beast Titan. When their commanding officers die confronting the Titans, Ymir speaks with Christa, reminding her of a promise they made to each other during their training days. Taking a knife from Conny, Ymir slits her palm and transforms to fight the Titans at the base of the castle.