Illithids, also known as mind flayers, are a fictional race of creatures in the Dungeons & Dragons role-playing game. They are characterized by their octopus-like heads, which feature tentacles, and their ability to consume the brains of other beings. Illithids are known for their powerful psionic abilities, allowing them to manipulate minds and control others. These creatures typically dwell in the Underdark, a vast network of underground caverns and tunnels. Illithids often form communities called colonies, where they work together to achieve their goals. They are often portrayed as malevolent beings, seeking to dominate or enslave other races to further their own ends.