Recall earlier, the narration noted that Matt thinks of the trail markers as a fun game. This is why he’s so excited to point out the beaver to Attean—he’s finally “won.” However, Attean’s dark mood helps to show Matt that little about Attean’s life is fun and games. He’s an orphan, his tribe is being slowly pushed out by settlers, and on some level, Matt seems to realize that he, as a settler, is part of the problem.