Sonic and the Black Knight is a Japanese manga written and illustrated by Hirono Makoto, and serialized by Dengeki Nintendo DS. It is based on the video game of the same name. It was released on 12 March 2009 which was the same day the game's release in Japan occurred.
In the beginning of the story, Merlina is being chased in the game by King Arthur. Arthur traps Merlina with a whole bunch of demons he summoned. Merlina, knowing she is trapped for good, summons Sonic from his world to save her. Sonic, knowing how to defeat enemies, defeats the demons and counters King Arthur. He goes up to him, but Merlina pulls him back and transports Sonic and herself away.