Skruuvi
Skruuvi is a Finnish variant of Vint, and it became common in Finland while it was a part of Russia. The rules of Skruuvi diverged slowly from Vint, and the rules were codified in the 1940s in the books Skruuviopas by the pseudonym O.L. and Uusi täydellinen skruuvipelin ohjekirja by the pseudonym E.N. Maalari. Skruuvi is still played in Finland as a niche hobby whereas Vint is not played in Russia. Helsingin Suomalainen Klubi still organizes annual Toro Skruuvi tournament in honour of Arvo Ylppö, an enthusiastic Skruuvi player.
Skruuvi uses a bidding system similar to bridge, but the emphasis of the bidding system is more in signifying individual high cards, similar to slam-investigating cue bids in bridge.
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