Kubb

If you are proficient with a gaming set, you can add your proficiency bonus to ability checks you make to play a game with that set.

Playing Kubb

You start with a pool of 3d6’s, 4d6’s if you’re proficient and 5d6’s if you have Expertise.
Each round is a contested Intelligence (Kubb) roll. Then you roll your dice pool. The winner of the contested roll can remove one of their opponents' three highest dice that’s rolled number is lower than one of their dice. If the dice are equal you can choose to remove both dice or none. This dice is removed from their opponents pool.
The game ends when one player has no dice left in their pool. Variant Speed Kubb:
After the winning player removes a dice that is lower than theirs the loser can do the same, with their remaining dice.
Cheating:
You can try to cheat by rolling Dexterity(Sleight of Hand) in place of your Intelligence(Dragonchess). Compare that roll against the other players Passive Perception. If it’s equal or lower, they notice your cheating. If you are playing the normal rules any cheating rolls are at a disadvantage.
Example: Asinaras wins the dragonchess roll and Banari loses. They both roll their die pools. Asinaras is proficient so they roll 4d6 getting 2, 5, 4, and 2. Banari isn’t proficient so they roll 3d6 getting 4, 6, 3. Asinaras can remove the dice that rolled 4, or 3, but not the dice that rolled 6. Banari now has a pool of 2d6.
The next round they roll again and Barnari wins. Asinaras rolls 6, 5, 4, and 1, Banari rolls 3, and 2. Banari can’t remove any dice as the three dice at risk (6, 5, 4) are all higher than their highest dice (3). Asinaras has a pool of 4d6’s and Banari is still at 2d6.
At the third round, Asinaras wins the contested roll. Asinaras rolls 5, 4, 3, and 2, and Banari rolls a 5 and 5. Asinaras chooses to remove her 5 and one of Banari’s 5’s, leaving Asinaras with 3d6 and Banari with 1d6.
At the fourth round they decide to switch to Speed Rules. They roll and Banari gets lucky, winning the roll. Asinaras rolls 5, 3, and 2, and Banari rolls a 3. Banari can only remove the 2, so they do. Asinaras, playing speed rules, now gets to take one of Banari’s dice that are lower than one of theirs, using the 3 or 5, they remove Banar’s last dice.