Sub-Zero also uses the Ice Daggers in his Cryomancer variation in Mortal Kombat X, though, unlike Frost, his Ice Daggers have a much smaller presence in his moveset, appearing only in one of his special moves.
The daggers are created by Frost's ability to control the ice element. Due to the fact her power over ice is inferior to Sub-Zero's, the daggers are the full extent of her ability to form solid objects, while Sub-Zero is capable of creating larger objects such as a sword.
In Mortal Kombat X, Sub-Zero uses the Ice Daggers to deliver quick, precise, and deadly strikes to his opponents during his Polar Puncture special move and Pick Your Brain Brutality. Sub-Zero's daggers also appear smaller and less serrated than Frost's.