Ex

Ex is the Guardian of Time and Space, and the former King of Tetris. He is also Ess' biological father. He makes his debut in Puyo Puyo Tetris as an unlockable character. His presence is first foreshadowed in Chapter 6. During Ess's visions while training, she encounters Zed. But instead of Zed's normal behavior, she hears a message from a mysterious voice, talking about regretting leaving Ess alone and creating Zed as a substitute. Distressed, Ess challenges Zed to a match, afterwards shrugging it off as an impostor. However, he would appear to O, saying that he's the one that receives Tee's reports and apologizes for causing the worlds to merge with each other, requesting for O to stop him. His proper appearance is in Chapter 7. Ex is the only character introduced in Puyo Puyo Tetris not to be based on a Tetromino.