First introduced in mid-2017 at San Diego Comic-Con, Power of the Primes, in keeping with the previous two toylines, features a complex line-wide gimmick that encompasses every size class: all figures include a small Powermaster-like "Prime Master" figure that can interact with their larger partners in a variety of ways. Deluxe and Voyager-class toys can attach the figure to their bodies, while Legend-class figures come with Pretender- styled Decoy Suits.
Leader-class toys each come with their own unique Matrix, which can mount any Prime Master. Each Leader has a second gimmick: each toy comes with a smaller figure that can "power up" into a Prime.
Fans were allowed to choose a character that would receive a toy and influence the story. Optimus Primal won. [1]