This Swedish game, best for about 4 to 6 players, is played with Swedish Kille cards. These come as a 42 card deck, without suits, but with two of each of the 21 ranks, which from high to low are Harlekin (joker), Kuku (cuckoo), Husar (hussar), Husu (pig), Kavall (horse), Värdshus (inn), 12, 11, 10, 9, 8, 7, 6, 5, 4, 3, 2, 1. Kransen (wreath), Blompottan (flowerpot), Blaren (face).
Each player is dealt 5 cards and tricks are played. Any card can be led, and subsequent players must either equal or beat the highest card so far played to the trick or play the lowest card in their hand. The object is to have the lowest card after four tricks have been played.
Rules for a version of Krypkille can be found on Joachim Parrow's Kille page.