Terden was a Sansha scout. Before he joined the Nation, he worked at an old colony under the man Melvue, and appears to have lived with Fermar's family. It's unclear when Terden joined the Nation, but he appears to have been present at the old colony when Melvue sold it out.
When he met Fermar at the new colony, he was dressed in black, stylish in a fairly classical way and covered with a mop of dark, curly hair; noticeable, all in all, but not memorable. He was younger than Fermar by at least thirty years, but didn't carry himself with the same bullish assurance. Fermar moved like a man used to high gravity; this one sidled like someone expecting the sky to pick him up at any time.
As an advance scout, Terden's job was often to approach colony managers like Fermar and ask them to cut a deal with the Nation to minimize casualties. Fermar shot and killed him before enacting his plan to destroy the Sansha raiding party in a trap.