Reshare from my old account. Arrow keys to move, space to use the character’s ability, and 1-4 to switch between characters. Each character’s attack has a different effect on each boss, but usually fireballs will do more damage, while swords can pierce armor and ice has longer range. Likewise, each boss will become progressively harder to defeat.
All by be. There is a similar project on scratch, but that is by my old account, and is therefore my property.