In short
- Every Sunday, 16:00 to 18:00.
- Odd weeks are castle siege, even weeks are Territory War.
- Registration closes on Saturday at 23:59.
One fixed hour a week when the whole server is in the same place. Sunday, 16:00 to 18:00, always.
Odd weeks are castle sieges, even weeks are TW. Alternating avoids what happens on every server: the same clan defending the same castle every Sunday until nobody registers any more.
In week 1 there is no castle in play at all. Aden and Giran come in on week 2, Goddard and Rune on week 4, Innadril and Dion on week 6, and all nine are only in play from week 8.
Every castle region has one, and it is the one the clans of that region fight over:
They have not gone anywhere. They are there with their NPCs and their doors, and anybody who walks past one finds an ordinary place. What they do not do is take a siege registration, so they never have an owner. The reason to concentrate is the reason castles open in stages: a siege spread thin is one clan alone hitting a door, and that is not a siege.
Whoever wants to fight on Sunday registers by Saturday night. That exists so you know who you are playing against before you build the team.