MIAT Mongolian is the main international airline of Mongolia. The airline is quite small, only 3 737s and 2 767s, along with orders for a few MAXs and a 787. They do a lot with this small fleet however, serving several Asian countries from their base in Ulaanbaatar, and even having flights to Germany.
Currently we have no Mongolian airlines in Infinite Flight, leaving the country unexplored.
The 767 is badly in need of a rework, and I hope that when the devs get to it, this awesome livery is included.