Jackalstripe

Spoilers ahead! Jackalstripe is an NPC. He can be found in the Hunting Grounds after Level 4 is complete.

After Level 4
Jackalstripe appears in the Hunting Grounds where the protagonist can talk to him. Jackalstripe will describe how he lost three pieces of equipment while in the Dark Forest. If the protagonist shows interest in the items, Jackalstripe will name the items he lost before leaving the hunting grounds. The game will then make the lost items available inside treasure chests that can be found in future levels.

Should the protagonist find all three items, Jackalstripe will reappear in the Hunting Grounds where the protagonist can attempt to return the items. However, Jackalstripe refuses the offer, claiming that he already has an even better set of equipment. He then decides to let the protagonist keep the three items as compensation for their efforts. The three items will then be available for the protagonist to use and equip.

Note that the first of the lost items appears in level 7. Should the protagonist accept the quest after level 7 has already been completed, the sidequest will be impossible to complete.

After Level 7
If the Cedarspots sidequest has not been failed, Cedarspots and Jackalstripe have a conversation off-screen, where it is revealed that Jackalstripe has feelings for the protagonist's sister Stonefall.

After Level 10
Jackalstripe is taken as BoulderClan's prisoner alongside Stonefall and Mudbranch. The protagonist must complete Level 11 and navigate the hidden-wall maze at the edge of BoulderClan camp to rescue them.

Post-Game Quest
Jackalstripe protests Stonefall's decision to accompany Fallingbrook on his journey to the Point of Stargazing, but Stonefall remains firm in her decision. Stonefall is curious about the source of his concern; she will generally remain indifferent regardless of the protagonist's suggestion.