Frostmourne (Icecrown Citadel)
The Frostmourne subzone is a spiritual realm inside Frostmourne where a player is transferred into if a player survives the Lich King's Harvest Soul ability. King Terenas' spirit fights with a Spirit Warden inside. Players leave Frostmourne when the Spirit Warden is dead.
The Blades of the Fallen Prince subzone appears to be the continuation of the spiritual realm.
- Patch 3.3.0 (2009-12-08): Added.