The AN94 Mythology is an upgraded variant of the AN94 ONCA. It was originally released in the Halloween Havoc Update in the capsule shop and has been there since. Compared to the ONCA, it has higher damage, range, recoil control and fire rate.
See AN94 ONCA
The exterior has a brown, leather-looking base coat with a huge amount of detailed engravings along the entire base of the gun.
This gun is only a 2-shot burst gun, so you should aim for the head as it is quite accurate and high damage, so you can drop someone quite quickly as long as you are accurate.