Ether Castle is the most coveted Region of Territory Wars.
To control Ether Castle you must have an alliance of level 4 or higher that currently controls one of the 3 main regions. Speak to the Local Agent of the region you control for a Proof of Dominance, then go to the Ether Castle Agent in Pokari City in Realm 8 to register.
Registration for Ether Castle Begins at 20:00 Wednesday nights and ends at 24:00 Thursday nights. On Saturdays, prep time for the defending Alliance begins at 17:00. During this time, teleportation service is unavailable. The battle for Ether Castle Begins at 18:00.