Matthew Christopher Miller, known professionally as Matthew Mercer and Matt Mercer, is an American voice actor involved in English dubs of Japanese anime, as well as cartoons, films and video games. He is best known for voicing Prince Demande in Sailor Moon and its 2014 anime adaptation Sailor Moon Crystal, and for being the current voice of Spyro the Dragon in the Skylanders video game franchise. He is also known for his role as the Dungeon Master of the Dungeons & Dragons webseries Critical Role.

For Disney, he voiced Tony Stark/Iron Man in Marvel Disk Wars: The Avengers, Captain America in Marvel Super Hero Adventures: Frost Fight, and Wedge Antilles in Disney INFINITY: 3.0 Edition. He also provided additional voices in Monsters University, and voiced Foreteller Ira in the χ Back Cover cinematic cutscenes of Kingdom Hearts HD II.8 Final Chapter Prologue, Hercules in the Avengers Assemble episode "The Incredible Herc", Aleksei Sytsevich/Rhino in Spider-Man, and Luke Skywalker in Star Wars Battlefront II.