This game was made as part of a 24 hour game design jam between some of my friends.
To play the game, you need a deck of cards and a 20-sided die. Take your deck and set aside cards with a face value of 6 through 10, Jack, Queen, and King. For this game, Aces count for 1. Add a single 10 that you put aside back into the deck for a total of 21 cards.
To start a round, shuffle and deal 3 cards facedown to each player, then deal one card face up. That number is the total. Then, alternating turns, each player can choose to do one of two things on their turn. First, they can choose to add a card from their hand to the total; or they can choose to go for it. When a player goes for it, they are trying to roll equal to or higher than the total. However, when they declare this action, the other player gets to add a rider from their hand or blindly from top of the deck. The rider increases the target value of the total before the roll. The player who starts the round cannot go for it on their first turn.
There are many ways to score in this game. When a player goes for it, on a success, they gain an amount of points equal to the total. For instance, if the total is 11, and the player rolls a 19, the player gains 11 points. However, if the total, before the rider is added, is 9 or higher, the points earned by the player who went for it are doubled. If the player chose to go for it and does not hit the target number, the other player gains 10 points.
Additionally, you can score by busting the total. If you play the card which brings the total to 20 or higher, then you gain 5 points. If the card you play makes the total exactly 20, you gain 10 points instead, but give the other player an opportunity to steal. When this happens, the other player rolls the die. On a roll of a 20, the player steals all that player’s points.
Additionally, included below is the game design document including the design pillars.