Chaos Castle

Chaos Castle is fought for glory and prizes, and it has a single winner. When you enter, your character takes on the look of a guardsman, the same look the monsters inside have, so nobody can tell who is who. Only your appearance changes, not your stats; a sword, staff or crossbow on the disguise hints at your class. Your own character is shaded brighter so you can find yourself. At least 2 players in the same level range are needed; if only one shows up, the fee is refunded and that player is sent out.

• Buy an Armor of Guardsman from town shops: the guide names the Wandering Merchant at Lorencia's south gate, the Craftsman in Noria and the Wizard in Devias.
• Right-click the armor to see when the next game opens, and left-click it when the timer shows the castle is open.
• You are sent to the castle that fits your level and the entry fee in Zen is taken. Players flagged as murderers cannot enter.
• Since the Season 21 update the entry brackets are the same as Blood Castle and Devil Square: 50–399, 400–799, 800–999, 1000–1199, 1200–1399, 1400–1599 and 1600 or higher.
• Since the Season 20-2 update entering on a mount, with a Transformation Ring on, or as a party is allowed. The mount and ring only give their stats, not their look, and your party stays formed.

• Everyone is an enemy, so no PvP setting is needed. During the waiting time you can move but not attack.
• Chat works while waiting but is switched off when the fight starts. Personal shops close, and guild wars or duels cannot be requested.
• Buffs only work on yourself, and damage between players is cut to 50%.
• Monsters fill the castle when fewer than 70 players join, and their number changes with the number of participants. Some explode when killed, knocking back and slightly hurting anyone next to them.
• Points: 2 for each monster and 1 for each player you kill.
• The floor shrinks from the outside as fewer players and monsters remain.

• You die when a monster or player brings your HP to 0, when you fall off the castle, or when a trap brings your HP to 0. You then revive in Devias.
• Traps start closing in when fewer than 50 players and monsters are left. They ignore defense, and the guide says they can kill outright whatever your level.
• The game ends when every other player is dead, or when all monsters are dead and one player is left at closing time. If more players are still alive at the end, points decide the ranking.

• 80% of all entry fees is handed out at random through a draw when the game starts. Example from the guide: 10 players in castle 1 pay 25,000 each, so 200,000 Zen is given out.
• The last survivor wins a Jewel of Creation, a Jewel of Life or a Jewel of Chaos. In castle 1 the prize is instead Jewel of Bless, Jewel of Soul or Zen.
• Monsters here do not give their normal drops; the guide lists jewel drops instead (1 Jewel of Bless per castle, 1–2 Jewel of Soul and 2–4 Jewel of Chaos depending on the castle, plus Zen by monster level).
• Master-level characters can also earn a Mastery Box via the Gremory Case, based on individual contribution: monster kills, player kills and victory.

A monthly tournament version of this event is covered in Survival of the Fittest.