Formling Leader

The Formling Leader is the leader of the Formlings, who also decides on those who are ready to find their animal form.

The Last of the Formlings (flashback)
When twin siblings Kataru and Akita were having their selection ceremony, it was briefly interrupted by Vex, who self-exiled himself when he unable to find his animal form, and the leader reminded him that he left on his own accord. Vex then attempted to persuade the Formlings to join him, saying he had found an Elemental Power, but they all refuse with Vex threatening them that he will be back as they leave. Later that night, he does return alongside the Ice Emperor and Boreal, who freezes the Formlings, including the leader, except for Akita and Kataru.

Awakenings
Although he isn't seen, the Formling Leader was among those freed from Zane's curse when he destroyed his scepter. He, alongside King Grimfax, agreed to banish Vex further away.

Trivia

 * It is unknown what his animal form is.