弱者の剣 (Jakusha no Tsurugi, "Sword of the Weak") is the first game from Polygonotes. It resembles the classic card game Daifugo but adds many twists.
At the start of a round each player is dealt six normal cards and one Sword of the Weak card. Normal cards have two numbers on them, one blue and one red, that always add up to nine, as well as a colored symbol in the middle. The Sword of the Weak has a different pattern on the back and its red and blue numbers are both one.
Your goal is to play all your cards. Each turn you have to either pass (and draw a card) or play cards to the middle. In order to play cards to the middle you have to have a higher total than the previous hand, and whether you use the red or blue numbers depends on the Scales card by the deck - it starts on blue, but every time a Sword of the Weak is played it's flipped. Being lucky will help you play larger hands, but in order to win you'll have to correctly time when you play your Sword card for the greatest advantage.
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