The Iluzija was mutated as such to closely resembles a serpent in its body shape and mannerisms, though enormous in size. It was originally a human that was exposed to the C-Virus. It was easily able to fling an average-sized human male with great force. Instead of two primary fangs, the Iluzija seems to have a line of thick fangs along its jaw, that bend forward similar to a viper's as it opens its mouth. The Iluzija appeared to be blind due to the apparent lack of eyes, or at least partially blind, and as such resorted to use its heat-detecting sense to locate its prey.
The most threatening ability of the Iluzija is its ability to blend in almost perfectly with its surroundings. While doing so, the snake is nearly impossible to see, with only a mild rippling haze visible when it moves.A flaw in this ability is that the inside of its mouth becoming completely visible when it opens to prepare for an attack.