Reference

The game of Kaschlan is not widely documented, and specific information on how the trump suit is determined is scarce. However, given its similarities to games like Durak and Hund, which often involve a system of determining trump through the dealer revealing a card from the deck, it is likely that Kaschlan follows a similar method. In many traditional card games, the trump suit can be established by turning the next card in the deck face up after the deal, or sometimes it's pre-determined before the game starts.

For more detailed rules on Kaschlan, you might explore resources on related card games or look into historical game archives that document rules for classic card games.

You can read more about Kaschlan itself on its Wikipedia page.