The Jaw Titan was one of the Nine Titans with a ferociously powerful set of jaws and claws that were able to tear through almost anything. Due to its small size, it was known to be one of the fastest out of the Nine Titans.
Abilities: Those who held the power of the Jaw Titan demonstrated significant amounts of speed and agility in their Titan form. They could even move fast enough to catch most of the other Nine Titans off guard. Though the Jaw Titan was relatively small and weak, its mobility excelled in terrain such as the Forest of Giant Trees.
History: The Jaw Titan, like all of the Nine Titans, was brought into the world after the death of Ymir Fritz. In the 1,700 years following her death, the Jaw Titan was held in the possession of one or several of the warring Eldian houses subservient to the Founding Titan. After these seventeen centuries when Karl Fritz, the 145th king of the Fritz family, abandoned the conflicts of Eldia and relocated to Paradis Island, the Jaw Titan was taken by the nation of Marley during the Great Titan War.
Story: 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.
Source: Jaw Titan (Anime), available under CC BY-SA 3.0.