Spoiler: I think, Rock is another Radiant, “Stonewarden”. Evidence: 1) cooks and meals build team cohesion 2) when we get a view of his thoughts they are concerned with others”cohesion” and counter 3) “tension” his family and past. 5) His name is “Rock” 6) He pulled the shard bow “tension/ cohesion”. 7) Body focus “bones” - horn eaters
I rest my case, “Watch the Lupin astound you.”
O almost forgot, rejected shard blades like Kalidan didn’t feel right.