That's troubling. Set is powerful in battle, but he's fragile in a myriad of ways. Whatever could've killed him...

[Also the question of what happened to his Shard if he was dissipated?]

I'll try contacting him via Communion throughout the next few days. If his Shard has been returned to the Tree, likely he'll return in a few days. Otherwise I can search Alenroux for any sign of him there.