Infiltrate is 1 of 3 daily Missions available in the game. By default, you are pitted against a randomly picked player-owned army. Their Power can vary notably, from weak to overwhelming. The reward for winning the mission is 4 Credits.
Should you deliberately engage another player in Pick a Fight! session or be attacked by anybody else, this type of mission will feature your previous opponents depending on how often you fought, no matter what Power level you both are.