The Red Deep Nightmare is a variant of the Deep Nightmare creature from Sonic Unleashed. This enemy appears in the nighttime stages of Sonic Unleashed and is the strongest Nightmare variant in the game.
Red Deep Nightmares look much like the regular Deep Nightmare, resembling humanoid chameleons with thick forearms. However, their bodies have a dark, reddish colouration to them and they sport cyan-coloured eyes and markings on their forearms.
The Red Deep Nightmare's behaviour and abilities are similar to the standard Deep Nightmare, though their attacks deal more damage and they are generally more resilient, making them more difficult to defeat.