Attach to a Noble hero or Aragorn. Attached character gains the Gondor trait. If attached character is Aragorn, he gains the Noble trait.

Action: Exhaust Elessar to choose an ally that is defending an attack and shares a Trait with the attached character. Either ready that ally or give it +1 for that attack.

“Say not The Lords of Gondor. Say The King Elessar.”
—Prince Imrahil, The Return of the King