In the quest "A Relic Reborn (Curtana)", during the part where you are supposed to slay Amal'jaa in Zahar'ak, the quest log on the side of the screen erroneously displays "Zahar'ak Archers" where it should say "Zahar'ak Thaumaturges".
The quest itself is unhindered, and has the quest icon above the heads of the Thaumaturges and not the Archers. Simple text error.