The Spiderchest is an Unversed that is found in Kingdom Hearts Birth by Sleep. It likes to camouflage itself as a normal treasure chest in order to lure in its victims, but there is always some detail that it fails to match.
A Spiderchest's body, true to its name, resembles a red treasure chest with black highlights and a black lock. It has yellow "teeth" lining the lid of the chest and three white, zig-zagging, bladed legs. The Unversed's spherical, black head is protected inside the chest. Its red eyes are set in a happy expression and the Unversed symbol adorns the top of the chest's lid. It is able to near-perfectly disguise itself as a large treasure chest, regardless of the world it is in. As such, its most common appearance resembles the default Treasure Chest design.
In Kingdom Hearts Birth by Sleep Final Mix, the red on the Spiderchest's body becomes blue, the black lining becomes gold, its "teeth" become silver, and its legs become black. The overall design now resembles a Treasure Chest from Castle of Dreams.
The Spiderchest shares its skill at deception with the Mimic from Final Fantasy, an insectoid enemy who also takes the shape of a treasure box in order to surprise anyone who tried to open it. It draws its name from these characteristics, with the first part of the name, "Spider", alluding to its origins from Mimic, with the latter part, "chest", being a reference to its major design as a chest.
A Spiderchest, while large, is quite easy to defeat. It will mainly hide as a treasure chest, attacking only when a player foolishly tries to open it. Its main attacks are to stab players with its legs or burrow underground to attack from below. Command Styles and Shotlocks are good for dealing with multiple Spiders. Magnet magic is also effective. It can also spit a poison attack at the player, that becomes a pool a of poison, dealing poison status on impact.