Pretty easy. You have Isildur with Narsil, Hunters ring, a lot of gondor artifacts and coat of mail or footman's armor. Other than that a lot of defender + companions could help...
First off, that's not "pretty easy." It is plausible, but not "easy."
If the maneuver phase is skipped, you are likely going to lose out on the ability to become defender +1 unless the character's game text allows him or her to be defender +1 (i.e., Aragorn, Heir to Elendil or Eomer with
Firefoot). You can't use the Hunters ring if
Cavern Entrance is played, or at least to my understanding.
-wtk