Guest Stars Bumper Robinson voices Falcon Laura Bailey voices Black Widow Jack Coleman voices Doctor Strange Isaac C. Singleton, Jr. voices Thanos James Mathis III voices Heimdall Trevor Devall voices Rocket Raccoon Kevin Michael Richardson voices Groot Will Friedle voices Star-Lord Laura Bailey voices Gamora Bumper Robinson voices Armored Army Roger Craig Smith voices Television Announcer Uncredited Phil LaMarr voices Dormammu