Every castle has a Steward next to the entrance of the castle hall. Only the guild master can use his menu:

• Invest in Economy and Invest in Defense (see below).
• Summon Guardians to protect the Emperium.
• Hire / dismiss the castle Kafra.
• Go to the master's room: treasure room and the lever to the realm's Guild Dungeon.
• Claim the WoE reward on the day a War of Emperium ended.

Both go from 0 to 100. The guild master can invest twice per day in each one; the second investment of the day costs 4× the price. Investments are applied every day at 00:01 Server Time.

Defense makes the Emperium and the guardians tougher: each point gives the Emperium +1,000 HP and extra DEF/MDEF (about 168k HP at 100 defense).

When a castle is lost, the new owner keeps it with −5 Economy and −5 Defense and the investments of that day are lost – defend it and the work of your guild stays.

Zeny per investment for each block of 5 levels (first and second half of every column). Second investment of the day: ×4.

Each castle has 8 guardian slots (Soldiers, Archers and Knights, the mix depends on the castle). Hiring one costs 10,000z and needs the guild skill Guardian Research. They appear at once and stay until they are killed – a dead guardian must be hired again.

• Strengthen Guardian is what makes them scale: with it, guardians get extra HP from the castle Defense, plus ATK and attack speed. Without it they keep their base stats (Soldier 15,670 HP, Archer 28,634 HP, Knight 30,214 HP).
• In the Sograt Desert (Morroc) castles guardians get half of the Defense HP bonus and no extra DEF.
• If you conquer a castle without Guardian Research, the previous owner's guardians are removed.

Level 90, Earth 1, 68,430 base HP (more with Defense). There are no guardian stones or barricades: the fight is for the Emperium room.

• Only members of a guild with Approval can attack it; players without a guild cannot.
• It can be hit with normal attacks and a few skills only (Triple Attack, Gravitation Field, Makibishi). Mercenaries cannot attack it.
• Breaking it gives the castle to your guild: the Kafra is dismissed and the investments of the day are lost.

The master's room gives access to the castle treasure room. The contents of the treasure chests are still being defined – they will be announced before they are enabled.

• Castle Kafra: 10,000z to hire, needs Kafra Contract. Storage, Cart (800z) and Teleport (200z).
• Guild Dungeon: the lever in the master's room takes the guild to the dungeon of the realm – Payon: gld_dun01, Aldebaran: gld_dun02, Prontera: gld_dun03, Geffen: gld_dun04, Morroc: gld_dun05 (Maya, Phreeoni and Shiny monsters).
• After every WoE, online members of the owning guild receive a Recruit Siege Supply Box per castle (25 WoE White Potions and 10 WoE Blue Potions, one per IP).
• On the day a WoE ends the guild master can also claim the castle reward at the Steward: 500,000z, 1 Old Card Album and 5 Old Blue Box.
• During WoE, players who are not of the owner guild are kicked from castles that are not in war.

Guild skills have a 5 minute cooldown after relogging. Guild auras work on every map and do not affect the guild master. Up to 3 alliances per guild.

• Invest in Defense every day and learn Strengthen Guardian: they are the biggest advantage of a defending guild.
• Re-hire dead guardians right after the war – a castle with empty slots is an easy target next week.
• Use the Guild Buff Manager in Prontera to level the guild: guild levels 10–50 give EXP/Drop, weight, boss damage and boss resistance bonuses to every member.
• Keep zeny for the second (×4) investment only when a castle is close to a new Defense block.
• Check the schedule above: only the castles listed in a session can be attacked in it.