With help from your contact in Radiata, you infiltrate Castrum Abania with a group of fellow adventurers.
How to Unlock
The 4-player dungeon Castrum Abania is unlocked by the level 69 Main Scenario Quest The Price of Freedom.
Magitek Fire II is a circle attack on a random player. Move out of the circle attack marker to avoid it.
Magitek Fire III damages all players.
Magna Roader will sometimes use Wild Speed, a series of line attacks back and forth across the area. 12th Legion Optios will appear and start using cannons to hit players with Magitek Pulse, an unmarked circle attack. Defeat the Optios quickly, then check on one of the cannons and it will add Magitek Pulse to your hotbar or crossbar. Use this attack on Magna Roader to stop its Wild Speed attacks.
Defeat Number XXIV
Elemental Overload damages all players.
If the boss has the "Fire Loaded" status, Discrete Magick is three cone attacks with three safe spots between. Then the boss targets a random player with a stack marker. Unmarked players should stack together with the marked player to reduce the damage of the attack.
Then the boss casts Serial Magick, which creates two sets of alternating cone attacks with a stack marker at the end. Stand in one of the first safe spots, then as soon as the cone attacks go off, move to where the attack went off, while also staying near the player marked with a stack marker.
If the boss has the "Ice Loaded" status, Discrete Magick is a set of crosshatched attacks. Then the boss marks all players with circle attack markers that follow them. Players should spread apart from each other to avoid overlapping each other with their circles.
Then the boss casts Serial Magick, which creates two sets of alternating crosshatched attacks, with the following circle attacks at the end. Make sure to move to a safe spot before each alternating attack, while also avoiding overlapping your circles.
If the boss has the "Lightning Loaded" status, Discrete Magick creates two towers. Make sure that at least one player is in each tower. Then the boss marks all players with line attack markers that follow them. Players should spread apart from each other to avoid overlapping each other with their lines.
Then the boss casts Serial Magick, which creates two towers, while simultaneously targeting all players with line attacks that follow them. Keep your lines from overlapping, and make sure that there is only one player per tower.
Ketu Slash is a high-damage attack on the player highest on the enmity list.
Rahu Blaster targets a random player with a line attack marker. Move out of the line marker to avoid the attack.
Ketu & Rahu will place a circle marker on part of the area, and will mark a random player with a red circle and triangle. That player should move out of the way of other players to avoid overlapping them with their circle marker.
Inferno will move to the edge of the area and receive an Empowered Ketu status. This will add more effects to Inferno's attacks.
Ketu Slash will now inflict Bleeding status on the player highest on the enmity list in addition to dealing damage. The healer can use Esuna to remove the Bleeding status.
The Ketu & Rahu attack will consist of cone or circle attack markers, as well as a proximity marker on the ground, or marking one or more players with a following circles. Players should move away from the proximity marker while also avoiding the other attacks.
Enemies will appear, tethering to random players and moving toward them. Kill the tethered enemies before they can reach the tethered players, and kill the Packer before it can take the medicine to the end of the room.
If Inferno receives an Enhanced Ketu status, Ketu Slash will cause a Vulnerability Up status in addition to the Bleeding status and damage.
The Ketu & Rahu attack will feature larger attack markers.
Completing the Quest
Defeating the boss will complete one of the quest objectives for the Main Scenario Quest The Price of Freedom. There will be a cutscene. This one is important, so it is recommended to watch it either now or via the Unending Journey in an inn room.