IGMF stands for "I got my frags". Usually used in context of multiplayer FPS games.
In games like Rainbow Six Siege or CS:GO, where there is same amount of
people in your and enemy team. There is a funny analogy that If everyone gets one frag(
kill), the team will win. And when the team looses, the person who got a kill be like "I got my frags".
This phrase is usually used in a sarcastic manner.
People are aware that the analogy of 'if everyone gets one frag then their team wins' is flawed.