The Kriskov Gambit was a predefined move in the game of three-dimensional chess that involved a player moving their pawn next to their king.
During a game of chess between Data and Deanna Troi, Troi employed the Kriskov Gambit. As an observation Data stated that "the characteristic response to the Kriskov Gambit is to counter with an el-Mitra Exchange." However, because Data had already taken both of Troi's rooks, she missed her opportunity to successfully complete the Kriskov Gambit, by ultimately leaving her king vulnerable. Her response was completely unanticipated and she ended up proving a worthy opponent with a possible check-mate in seven moves. (TNG: "Conundrum")