Punchbox is an enemy mimic. He is named "Punchbox" due to his looks. He is, essentially, a treasure chest with two eyes sticking out from under the lid. On each of the box's four sides, he has a arm that he can hide inside the chest. On the ends are large spiked fists. When hiding, they withdraw inside the box itself, and can hide indefinitely. He can also subtly change the outside of his box, including color and texture. Punchbox is a construct.
Punchbox is fought in the second quadrant of Cole's Castle, outside the tower. He has 1,350 HP and 0 MP. Defeating him earns 1250 EXP, 1000 GP and a Box Fist. He's not particularly difficult, but may be harder the first time due to not expecting him.