Google’s famous doodles — the illustrations that show up in place of the Google logo nearly every day — have been known to take the form of surprisingly great games on occasion. Today’s doodle is no exception: Rise of the Half Moon is a strategy card game that celebrates the half moon point in October’s lunar cycle.

Each three-level playthrough starts with an empty 3×3 board connected by vertical and horizontal lines. Your hand consists of three random moon phase cards, and on your turn, you can place a card on the board. The aim is to pair matching cards, pair cards that combine to make full moons (i.e., a waning crescent with a waxing gibbous), or place cards in the order of the lunar cycle. The board itself changes and grows in levels 2 and 3, and if you beat the computer all three times, you can unlock a legendary card.

Those legendary cards are there to please the deck-building fanatics among us. October’s legendary cards include “Leonids Meteor Shower,” which destroys two random cards on the board when played; “Hunter Moon,” named after the supermoon that was visible on Oct. 17, destroys the cards on the board that are controlled by the Half Moon and returns them to the deck. Google told Polygon that there will be legendary cards for every month of the year so, eventually, you’ll have a pile of wildcards to choose from.

At the end of every level, you’ll get bonus points for each card that’s in play on one of your combos — which means, as the game progresses, you’ll find yourself racing to convert cards to your side before your turns are up.

Rise of the Half Moon is challenging not because the computer puts up a good fight, but because it’s tough to remember the lunar cycle and plan ahead for combos when you don’t know what your next cards will be. I’ve gotten up to a 13-card combo — which means I linked up the full lunar cycle, plus five more cards — and refreshed my understanding of the lunar cycle along the way.

The game is satisfying and just difficult enough to keep me engaged, but it’s so short and sweet i can play a few rounds without getting distracted from what I sat down to do when I opened google this morning.