Baneguards are skeletons, usually but not always human, which are animated by clerical spells to serve as guardian creatures. The create baneguard spell was originally researched by priests of Bane (of the Forgotten Realms setting), but in the years since the demise of that deity, the secret of the spell has been spread such that many other evil (and not-so-evil) deities allow their priests to use it.
Usually found as guardians, baneguards are identical in appearance to normal skeletons, but have additional deadly powers which they reveal in combat.