The Transformers are adding some serious star power to their line-up in 2018.

Machinima and Hasbro's Transformers: Prime Wars Trilogy is gearing up for its third and final act, and has announced that a couple of iconic voice actors have joined the cast. Mark Hamill (Star Wars, Batman: The Animated Series) and Ron Perlman (Hellboy, Sons of Anarchy) are both set for roles in the upcoming Power of the Primes series.

Hamill will be voicing the evil Megatronus in the series, though you won't have to wait for the new episodes later this year to get your first glimpse at his work. Megatronus debuts in today's episode, the final installment of Titans Return, and will return with a larger role in Power of the Primes.

Perlman, on the other hand, won't be appearing until the final act of the Prime Wars Trilogy premieres in the spring. He is set to voice Optimus Primal, though no details regarding his exact number of episodes were revealed.

Both Perlman and Hamill are well-known for their voice work, and both recently appeared in Trollhunters on Netflix. Perlman started as the series villain, while Hamill was introduced in Season 2, which was just released in December.

The cast of Transformers: Power of the Primes also includes Judd Nelson Wil Wheaton, Jaime King, Somoa Joe and Mikey Way.

Part 3 of the digital series will be streaming around the globe on go90 when it is released this spring.