The Red Nightmare is a Dark Gaia minion that appears in the Playstation 2/Wii version of Sonic Unleashed. This creature is an enhanced version of the standard Nightmare, bearing red-coloured skin and cyan-coloured eyes and body markings.
Aside from the visual differences, the Red Nightmare isn't much different from the regular Nightmare. It is, however, more durable and can take more damage from Sonic the Werehog's attacks. It can also stretch its limbs over a wider area and can block attacks by holding up its arms.