Design and code of a game that may not be so simple that you can consult at this address : https://mathildarnaud.github.io/fish-invaders/

Your mission, as a self-respecting crab, is to preserve your territory from incessant attacks by ruthless fish. To defend yourself, you will have to press the space bar, and to avoid enemy fire, you can move with the left and right arrows on your keyboard.

This game has been coded in HTML and JS. Have fun!