The "Teammate" Demon (Japanese: デーモン"Mii's name" Demon "Mii's name") is a large, muscular Imp-like creature and one of the boss monsters in the Dark Lord's Castle. The demon utilizes the face of the first-recruited Neksdor teammate, and proves to be a challenging adversary, possessing both huge strength and the ability to feed off of a Mii's fear.
After the player completes the game, the boss may reappear in a quest. This enemy fights exactly the same, except it is much more powerful.
The Hero, who is trekking the castle to save their friends, finally has found the fourth teammate in the castle. The teammate, however, is revealed to be faceless as the Demon appears, using the face of that party member. In-battle, the Demon is a powerful adversary, wielding a large, double-sided mace while flanked by two Naughty Imps. The Demon also has the notable ability to feed on the party's fear, causing them to become nervous and unable to fight. Even with these abilities, however, the Protagonist swiftly defeats the "Teammate" Demon, and rescues the fourth party member.
|Action name||Description||Chance to use||Hit rate|
|Attack||Whack a single Mii with the morning star.||75%||100%|
|Anxious||Feeds on a Mii's fear, which may cause him/her to become anxious. Anxious Mii characters will not do anything and may cling onto another Mii, preventing them from taking action and slightly boosting relationship.||25%||30%|
|One More Time!||Attacks three times per turn.||-||-|
- The Demon bears a striking resemblance to Hades from Kid Icarus: Uprising, as do the other demon enemies.