Beshmundir Temple is “end-game” instance (required players level 55) added in patch 2.0. To be able to enter this instance, your race must open gates to Silentera Canyon (which will be open if you race conquered both fortress on your side). Due to fact that Canyon is available to other race as well (if they conquer theirs forts), trying to enter instance may cause battles!

Last boss of this instance (Rudra), as well as sets which drop here, look similar to Dark Poeta ones (but a way of doing the instance is different – in Beshmundir instead of time and points combination we will have “normal” and “hard” modes).

Rudra’s Plate Set
Rudra’s Chain Set
Rudra’s Leather Set
Rudra’s Cloth Set

Weapons:
[Note, that items liked from AionArmory display incorrectly – they have manastones slots even if link doesn’t “show it”]

Shield
Polearm
Greatsword
Dagger
Sword
Bow
Mace
Staff
Book
Orb

Źródło: Drops from Beshmundir Temple on Korean PowerWiki.