This list of mythical creatures that begin with this letter and I am constantly gathering information from each continent, and is continually being updated.
Monocerus (Medieval bestiaries)
The monoceros was first described in Pliny the Elder's Natural History as a creature with the body of a horse, the head of a stag (minus the antlers), the feet of an elephant, and the tail of a wild boar. It has one black horn in the middle of its forehead, which is two cubits (about 1 m or 3 feet) in length, and is impossible to capture alive.
the monocerus is usually described as having the head of a stag, the body of a horse, the feet of an elephant, the Ttail of a boar, and a single very long black horn growing from the forehead. It makes deep lowing sounds. It is the enemy of the elephant and when fighting it aims its horn at the belly of its opponent.