The game uses a for rewards. When you finish the game on a certain difficulty, you receive one unlockable from that tier or lower.
If you grew up in the early 2000s, the name Chicken Invaders instantly conjures images of intergalactic poultry, fast-paced arcade shooting, and that quirky sense of humor involving fast food puns. Among the most beloved entries in the series, (formally subtitled "Revenge of the Yolk" ) stands as a fan favorite. It took the chaos of the first two games and expanded it with a deeper story, new enemies, and—most importantly—a treasure trove of unlockable content. chicken invaders 3 unlockables