Galacard is a Game Boy card game where you play against some aliens on Planet Ack. The rules might sound complicated at first, but they're actually pretty simple:

Each player starts their turn by drawing a Starting Card from their deck. Each card contains a number and a shape, but the other players can only see the latter. Your goal is to be the first player in the turn to get the highest number with a card of the same shape.  There's also a card in the middle of the playfield called the Power Card. Drawing a card with that shape gives you an advantage even over the most powerful Starting Card, but just like with the latter, the highest one always wins. To clear a round, you must win the exact same amount of times as the goal you chose. If you're still lost, make sure to check out the Galacard Strategy Guide!

https://bipedal-studios.itch.io/galacard