The displacer beast is a monster in Dungeons and Dragons. According to the Monstrous Manual from Advanced Dungeons and Dragons Second Edition, the displacer beast "resembles a puma with two powerful black tentacles growing from its shoulders." The Dungeons and Dragons Third Edition Monster Manual adds the information that the beast has six legs and glowing green eyes, blue-black fur and a taste for small prey. Displacer beasts get their name from their ability to displace themselves: a displacer beast appears to be about three feet from its actual position. Hence, any attempt to attack it is likely to merely cut through the air.
Displacer beasts run in packs, and are very destructive. They attack almost any creature entering their territory with their tentacles, claws, and teeth. They particularly hate blink dogs, another fictional, mammal-like race of creatures with a similar magical ability.