Some ideas:
- A big chicken with a missile launcher. There is 2 of it in the game: one ahoots big missiles, which explode upon impact or by hitting the bottom of the stage, with a damaging exploaion radius, and another which ahoots small homing missiles, which stay on the screen and follow you for a reasonable time, after which they explode with a small non-damaging explosion.
- A new, improved UCO (from CI3)
- A wizard chicken, which can summon other types of enemies (like the final bosses, but weaker)