The Purple Night by LostImmortal is a dark platformer game made for Game Boy Advance.
Your mission in the game is to save a lost soul and take them safely back to the afterlife. Your health bar is your sword. The more damage you take, the shorter your sword gets, making you more nimble and your attacks faster, but also increasing your risk. So, the question is will you choose to stay at high health but low mobility, or low health and higher mobility?