Chicken Invaders puts players at the forefront of a battle against invading intergalactic chickens, bent on revenge against the human race for our oppression of Earth chickens. In this episode, the chickens have constructed a gigantic cannon capable of launching planet-scale eggs against Earth, with the ultimate goal of destroying Christmas by encrusting humanity in an impenetrable wall made of egg white. Joined by an unlikely ally, players will travel to foreign, unexplored galaxies in an effort to locate and destroy the egg cannon before it reaches Earth.

The Christmas Edition is characterized by festively dressed chickens which attack relentlessly in colorful groups and meticulously choreographed formations. The chicken fray is punctuated by fights against massive enemies disguised as Christmas elves, Santas, and other well-known holiday figures. Major enemies are also appropriately decorated with rows of blinking Christmas lights. Christmas ornaments, bows, ribbons, bells, and holly fly everywhere during the heat of battle. Floating Christmas gifts can be collected in order to extend the arsenal at the player's disposal. There's even a suitably festive snow blizzard -- in deep space! On-screen action is accompanied by original renditions of popular Christmas carols, composed specifically for this episode.