Arzodius is the main antagonist and final boss in the Nintendo 3DS Streetpass Mii Plaza game Monster Manor.
Before the events of the game, Arzodius and several ghosts had made a deal with a scientist to return his deceased daughter in exchange for a passage to his world. However, Arzodius used the portal to take over the manor the scientist lived in and possessed the scientist.
During the events of the game, Arzodius is first seen (though only his arm can be seen) reaching out of the mansion with his arm and pulling the chosen Mii into the manor. He also does this to hired investigators. Afterwards, he is properly seen after the player reaches the 30th floor, in the scientist's old lab, where he first hits away Iris Archwall after she attempts to confront him, afterwards, the chosen Mii will get out whatever weapon they have and begins the battle against him. The fight against Arzodius is quite different than other battles, unlike other enemies, Arzodius is not weak to any element and thus the weapon's strength is the only thing that matters. After he is defeated, he will start glowing on the inside and then simply fall on the ground and fade away, completing the first half of the game.
Arzodius survived the first battle and is found on the 50th floor in the 2nd half of the game, however he is completely blue instead of red. Where Iris Archwall tells the player about Arzodius' deal with a scientist (as stated at the top) and than Arzodius possessing the scientist and taking over the manor, afterwards the exact same thing as the previous encounter occurs. After he is defeated the 2nd time, Arzodius will glow even larger than before and explode, destroying Arzodius for good and completing the 2nd half of the game.
- Arzodius appears in Super Smash Bros. for Nintendo 3DS as a trophy.