Parallax is an emotional entity and the embodiment of fear, the beast of the Yellow Lanterns. It looks like a giant yellow fly, and as an avatar of emotion, Parallax is seemingly made of pure energy. Parallax is the energy source of the Yellow Lanterns, it has immense power as one of the most powerful beings in the universe, and it can possess certain hosts and give them powers beyond imagination to spread fears. The famous Green Lantern Hal Jordan is once a host after the destruction of his town turning him ruthless. He easily defeated superman and many superheroes. Sinestro also once became a host and seems to get more control over Parallax since he is a user of the Yellow Lantern.