Ikonn is a mystical entity, he is often invoked by such sorcerers as Dr. Strange, to perform the spell known as "The Images of Ikonn".
This spell holds extreme power over reality and if it gains enough power, the illusion can become reality.
When it joined the Octessence to perform the Wager it took on the form of an insectoid/humanoid of a greyish color that was adorned with dark greenish spikes and grey-green eyes without pupils. Each limb ended with four claws, it had a proboscis instead of a mouth, but it must be assumed that the Master of Illusion's true form is far different.
He created the Ivory Idol of Ikonn for the Wager which later transformed Olisa Kabaki into the Exemplar, Bedlam.