The drop bear is a pesky creature, represented by a "K". Clinging to the ceiling of a given level of the Caverns of Creation, they cannot be detected by the player until they attack (even if the player has Sight Beyond Sight). If they successfully attack the player, the player will often be stunned for two to six turns-- enough time, generally, for the drop bear to make its way to a wall and disappear along the ceiling once more.
The drop bear's attack is repelled with one hundred percent accuracy by the pointy hat, which is destroyed in the process. A failed attack will stun the drop bear for one to two turns, at which point it will try to escape. As they generally have low hp, they can usually be beaten by a player whose collection of pointy hats give him an edge.
Defeating the drop bear will cause him to drop an item; playing on the dual meaning of its name, the drop bear can drop literally any item in the game, including items that are one-of-a-kind. (In theory, this also includes the Sasquatch Hide Armor, but since it disappears after being dropped, it's kind of a moot point.)