https://pirate-shell.itch.io/chicken-a

Chicken A is the only 2D retro-inspired platformer game where you can be both a chicken overlord and a cute chicken pet. Play through 4 action-packed levels, each giving you the choice to augment your chicken genetically. Based on your choices, your chicken can turn out to be anything you want!

(As long as that anything fits within 4 pre-determined ending options, that is.)