After meeting the force led by Lord Commander Jeor Mormont at the Fist of the First Men, Qhorin Halfhand selects Stonesnake, Harker, and Borba for a scouting party to ambush a group of wildling lookouts. They are joined by Jon Snow. They locate and surprise the lookouts, killing all but one of them. Jon is left to execute the wildling survivor. Jon does not return and they return for him. They pick up his tracks but are ambushed by wildlings. Harker, Stonesnake and Borba are killed while Qhorin is captured. Jon had spared the captive and she leads him into a similar ambush. Qhorin seizes the opportunity to insert Jon as an infiltrator in the wildling ranks by berating him for the deaths of the others publicly.
In the Song of Ice and Fire novels, Stonesnake is also a Ranger serving under Qhorin Halfhand. He is short and wiry man, near fifty with a grey beard. He is stronger than he looks, and has the best night-eyes of anyone Jon has ever known. He's dubbed Stonesnake for his ability for climbing mountains and cliffs.
Stonesnake leads the mission to scale the Skirling Pass at night to ambush a trio of wildling watchers. He and Jon kill two of the sentries (one of them is Orell). He expresses distrust in Ygritte and later informs Qhorin of what she told Jon.
In the novels, his fate is uncertain. After his horse panics and breaks its leg, he offers to stay behind and fight the pursuring Wildlings like Dalbridge, but Qhorin orders him to make it through the Frostfangs afoot to the Fist, and to tell Mormontwhat they saw. Jon watches Stonesnake goes away, and fears that he has no chance. Stonesnake has not been mentioned since. While it has not been confirmed that he died, according to the novels appendix he was lost afoot in the Skirling Pass.