Tried to find it by the pyramides, but found electric, plant, water, fire, dark and light only…
Think this should go in Neo Monsters General Discussion but since I’m here, Omegamid can be obtained through special events such as “A Challenge From the Developers” or in their live mission found under:
Online -> Ultra Evo & Events -> Live Missions -> Omegamid
Currently, neither of these are active. Your next opportunity to get an Omegamid is during “A Challenge From the Developers” that starts on January 1st. Be warned, the difficulty setting is Extreme. If you are unable to beat it, then your only other option is to wait for the actual Omegamid Live Event which is much easier to beat. Keep an eye on the News tab for such dates and details.