Chimera

Chimera is a minor character introduced in Shinyaku Toaru Majutsu no Index. They are a "bizarre magician", one of the magic gods who dwells in a territory beyond a certain layer of the world.

Etymology
In Greek mythology, a chimera is a creature that is part lion, part goat and part snake or dragon. Its body is that of a lioness, a snake or dragon head is its tail, and a goat head pops out of its spine in the middle of its back. It also breaths fire. According to the myths, it was eventually slain by Bellerophon with the help of the winged horse Pegasus.

Appearance
Nothing is known about what they look like.

Magic God Othinus Arc
They are mentioned in passing, alongside the Zombie girl, by Niang-Niang as one of the Majins present in the Hidden World with the rest of the true Gremlin.

St. Germain Arc
It is unknown where Chimera is when High Priest, Nephthys, and Niang-Niang decide to enter the world once again using Zombie's spell.