Dungeon set 5 items drop randomly (rarely) around the world starting on level 75 enemies and up until level 79. They also drop more frequently off trash mobs and assuredly from bosses in the Daily Quest dungeons: Imirian Ravine, Frost Swamp, Oasis of Zaara

Sets contain 6 items. The Wrist, Feet and Belt are all tradable. The Chest, Shoulder and Head are not.

Dungeon Set 5 (level 75-79)

{{ucfirst:Assassin} Assassin {{ucfirst:Barbarian} Barbarian {{ucfirst:Bear Shaman} Bear Shaman {{ucfirst:Conqueror} Conqueror {{ucfirst:Dark Templar} Dark Templar {{ucfirst:Demonologist} Demonologist
Darkshroud Berserker's Rendclaw Battlemaster's Baleful Nadiral
{{ucfirst:Guardian} Guardian {{ucfirst:Herald of Xotli} Herald of Xotli {{ucfirst:Necromancer} Necromancer {{ucfirst:Priest of Mitra} Priest of Mitra {{ucfirst:Ranger} Ranger {{ucfirst:Tempest of Set} Tempest of Set
Dauntless Rageflame Soulbinder Exalted Ravenwing Skyfury

Armor Sets
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Dungeon (Group) Dungeon Set 1 - Dungeon Set 2 - Dungeon Set 3 - Dungeon Set 4 - Dungeon Set 5 - Dungeon Set 6
Tier (Raid) Tier 1 - Tier 2