Adventure Time Love Letter is a game of risk, deduction, and luck for 2–4 players based on the original Love Letter game by Seiji Kanai, except re-themed with characters of the hit cartoon Adventure Time. Players are suitors trying to gain the affections of Princess Bubblegum (#8).

In a round, each player starts with only one card in hand; one card is removed from play. On a turn, you draw one card, and discard one of the two, using the power of the discarded card to try to eliminate other players from the round. If you're the last player in the round, or the player with the highest card when the deck runs out, then you score a point. The game is played until a player reaches a certain amount of points determined by the numbers of players.

The card art is styled to be Adventure Time characters "cosplaying" the characters from the Tempest version of Love Letter by AEG.

There are two differences in this version. Number 1 is a new win condition. If a player plays a "Hero" (#5), either Finn or Jake, and makes another player (including themselves) discard the other "Hero" card, they win the round. The idea is that you are reuniting the iconic best buds. Number 2 is, if you manage to win the round with a "companion" in your hand, you win 2 tokens instead of only one.