About DUEL BOY, from BoardGameGeek:
DUEL BOY is a trading card game with unique seven-card packs. The game was first distributed at the 2022 Fall Tokyo Game Market. The packs include seven cards for playing the game, one divider card, and a sticker the owner can wear to help find opponents to play the game.
The game was designed to be played while standing (for instance, while in line to buy a game) and does not require a table. After a match, the players swap two cards, with each player leaving with five cards they entered the game with and two of their opponent's cards.
After an initial shuffle of cards, a player has one chance to reshuffle, but otherwise must play their hand as it has been drawn. A game is made up of several rounds, and the first player to win three hands or cause their opponent to not be able to play a card on their first turn of a hand wins the game.
Players can play cards only from the rightmost end of their hand and must pay the cost of cards with the cards from the left end of their hand. Once per hand, a player can put the cards from their discard pile on the bottom of the deck - in the exact order they were discarded.
