Tenken and Kazuki, the co-leaders of the ANBU Branch, wishing to separate themselves from the Obsidian Palace and prison duty, relocated their base of operations to Ruins of Old Suna. Following the "Great Earthquake", it was viewed as even more important for the masked members of the shinobi forces to relocate to the underground, allowing them to be the first response to The Swarm activity that had recently picked up. The underground was a new frontier for the country, the ANBU wanted to be on top of monitoring the happenings of this new territory and how it could impact the village.