Mephone X appears to be the most robotic and mechanical Mephone to date, leaving little to analyze their lack of emotion. Although they do seem aggressive as seen in the post-credits scene in "hatching the plan".

Mephone X is a large black rectangular phone. On the left, they have two volume buttons and a ringer switch, and on the right is a power button. They have a large screen on their front which has a black and red wallpaper. In the center of the screen is a large red X.