Castrum Marinum (Extreme)

Raid Strategy Guide
Lyra Rose
Table of Contents


This guide aims to provide tips and strategies for defeating The Emerald Weapon in Castrum Marinum (Extreme).

The Emerald Weapon is the newest fight in the Sorrow of Werlyt series, available December 7, 2020 in Patch 5.4. Players must have completed the Quest Blood of Emerald and speak with the Warmachina Fanatic in the Lochs (X:11.5 Y:22.5). Players must be item level 500 or above to challenge this fight in a non-premade group.



One of:
i515 Emerald Weapon


Emerald Gwiber Trumpet
Faded Copy of the Black Wolf Strikes Again
Emerald Plating


Emerald Totem
Ten tokens can be traded in for a weapon of your choosing.


Pre-pull Preparation

Assign players to a pair at cardinals. These pairs can consist of any role. However, it can be better for melees if their partner is ranged.

Emerald Weapon is a two-part fight. Phase two has a checkpoint once you beat phase one.

Mechanic Overview

General Fight Mechanics

A moderate raidwide magical AoE.

A tankbuster on the MT that needs to be shared or invulned. It will also deal damage to DPS and healers in one of two ways:

  • In phase one, non-tanks will have to spread as they will have an unmarked AoE on them.
  • In phase two, non-tanks will be targeted with a thin conal AoE, so they should spread around the boss.

The two halves of the boss will split. If the top half remains, it will do Sidescathe. If the bottom half remains, it will do Expire.

Cleaves one half the arena – it will glow on that half.

A circle AoE around the boss.

An AoE marker that will expand.

Phase One

A moderate damage magical tankbuster on the MT.

The Emerald Weapon will spawn eight orbs at cardinal and intercardinal edges. These will either be yellow or purple. These orbs require two players each to soak the damage. Players cannot soak more than one of the same coloured orb:

  • Yellow orbs deal physical damage and inflict a physical vulnerability up debuff.
  • Purple orbs deal magical damage and inflict a magic vulnerability up debuff.

The Emerald Weapon will shoot rotating conal AoEs in the front and back, as well as expanding ring AoEs. Move along the rotation to dodge.

The Emerald Weapon will spawn mines on the arena. These will explode after they finish counting down. These mines can be pushed or pulled apart from each other if they have a magnet symbol above them. Opposites attract, and same repels.

A magical proximity marker on both tanks. These must be taken away from the party in safe spots from Magitek Magnetism mines. The safe spot does not change for tanks.

The Emerald Weapon will summon its hands around the arena. It will then do an untelegraphed donut AoE around it.

Two players will receive a marker on their head. When it resolves, the Emerald Weapon will cast a line AoE at them.

Phase Two

All non-tanks are marked with an arrow. When the castbar resolves, they will be pushed back across the arena in the direction of their arrow, emitting a line AoE. This will inflict a physical vulnerability debuff.

All non-healers will receive a cross shape or an X shape under their feet. When it expires, it will do AoE damage and drop a sword under them. This sword will do a line AoE in a cross or X.

The Emerald Weapon will summon swords that drop down into the arena in three sets. These swords will shoot AoEs in either a cross shape or an X shape. Players will have to dodge these AoEs.

A knockback from a marker.

The Emerald Weapon will disappear and the Black Wolf’s Image will take its place. This will cast several mechanics. Damage dealt to the image will be dealt to the Emerald Weapon after it returns.

The Black Wolf’s Image will summon airships at the west side of the arena. These will shoot circle AoEs across the arena in the order of dots above their head. It will also summon an airship south that casts Magitek Cannon at the end of the sequence, which knocks back from a marker.

Deals moderate damage to a non-MT player.

Summons soldiers north of the arena, which will shoot a line AoE across the arena. There will be one column with a soldier missing to dodge in.

Phase Mechanics

Phase 1

Emerald Shot
Optimized Ultima
Aetheroplasm Production
Emerald Beam
Magitek Magnetism
Magitek Magnetism
Photon Burst
Emerald Beam
Optimized Ultima
Bit Storm
Divide Et Impera
Aire Tam Storm
Magitek Magnetism
Pulse Laser
Optimized Ultima
Bit Storm
Divide Et Impera
Optimized Ultima
Full-Power Optimized Ultima

Enrage is a long casted Full-Power Optimized Ultima that occurs ~5:36 into the fight and wipes the party.

Phase 2

Divide Et Impera
Primus Terminus Est
Tertius Terminus Est
Legio Phantasmastis
Mechanized Maneuver
Optimized Ultima
Divide Et Impera
Tertius Terminus Est
Sidescathe OR Expire
Emerald Crush OR Aire Tam Storm
Legio Phantasmatis
Mechanized Maneuver
Rank and File
Secundus Terminus Est
Tertius Terminus Est
Expire OR Sidescathe
Aire Tam Storm OR Emerald Crush
Primus Terminus Est
Divide Et Impera
Full-power Optimized Ultima

Enrage is a long casted Full-power Optimized Ultima that wipes the party.

Fight Strategy

Phase 1

  • Pre-shield and regen the MT, as they will take a heavy buster.
  • Pre-mitigate and heal for Optimized Ultima.
  • Heavily mitigate for the Aetheroplasm orbs. Players will have to pop orbs in pairs. Pop orbs cardinally first, then come back into the middle for extra shields and heals. Rotate to pop the next set of orbs.
    • West and East should pop the second set of orbs first, as they have one option while rotating, while North and South have two.
  • Rotate in the direction the Emerald Weapon is. Make sure to dodge the AoE rings in the centre, then move into it. There will be two sets of these.
  • The party should stack where the two mines are being pushed apart for the first Magitek Magnetism. Tanks each pick a far open side and mitigate Photon Burst.
  • For the second set of Magitek Magnetism mines, the safe spot will be where two mines are being pushed apart.
  • Dodge Emerald Beam the same way as before.
  • Stay inside the boss hitbox for Bit Storm.
  • Tanks should stack and mitigate Divide Et Impera, or the MT should invuln it. All other non-tanks should spread out.
  • The boss will cast Split, and he will always cast Expire after. Get out as the castbar finishes.
  • Dodge the expanding AoE.
  • The third set of Magitek Magnetism mines are the same as the second set. However, players marked will have to bait the line AoEs away from the safe spot before moving in.
  • Heal the Optimized Ultima, and beat enrage. All mechanics are the same as previous – mitigate the tank buster, get in for Bit Storm, and heal up.

Phase 2

  • Tanks should immediately mitigate Divide Et Impera, or invuln it. All other players need to spread without overlapping around the boss.
  • Players should fan out to the edges of the arena for Primus Terminus Est. The best way to handle this mechanic is have all the arrows start Northeast or Southwest. Players can adjust to not overlap from there.
  • Tertius Terminus Est is the main mechanic of the fight, and happens three times. The bulk of this mechanic is that swords will drop in two intercardinal corners, two intercardinal corners, and the middle, the order of which will be random. Players need to stand in the path of the third sword AoEs and move into the first sword AoEs after they explode.
    • If the swords explode in an X, players will have to move either from the cardinal edge to cardinal inside or vice-versa.
    • If the swords explode in a cross, players will have to move either from the intercardinal edge to intercardinal inside, or vice-versa.
  • Joonbob has an excellent video on this mechanic, which can be viewed below.
  • The boss will then transition to the first Legio Phantasmatis phase.
  • The tank should pick up aggro on the Black Wolf’s Image. DPS it down, and note the order of which the airships fire.
  • You want to dodge the AoEs by going into the path of a higher numbered airship, and moving into the path of a lower numbered airship after the AoE has gone by.
  • After all the AoEs have gone by, press your knockback immunity or stand close to the mark to get knocked back. Heal up and mitigate if necessary, as it does damage and players may have taken vuln stacks.
  • The boss will do another Optimized Ultima into Divide Et Imperius. Mitigate and spread out.
  • The boss will do the second set of Tertius Terminus Est mechanics. It will cast Split, and either Sidescathe or Expire. Dodge as necessary. The mechanic it cast will determine which type of sword mechanic will occur next.
    • If Sidescathe was cast, the boss will cast Emerald Crush. Players must get knocked back into the safe spot to dodge swords, which will always be in one of two intercardinal positions.
    • If Aire Tam Storm (expanding AoE) was cast, players will have to move into the safe spot to dodge swords after the AoE goes off.
  • The boss will transition to the second Legio Phantasmatis phase.
  • In this phase, players will have to deal with airship exaflares while dodging line AoEs coming from the north side.
  • The MT should pull the boss north.
  • There will always be a higher numbered and lower numbered airship north. Stand in the path of the higher numbered one and dodge the three Rank and File AoEs – you will know the movement ahead of time based on which soldiers are missing.
  • Move into the path of the lower numbered airship while dodging Rank and File AFTER the AoEs have passed.
  • Quickly move back to the marker or use a knockback immunity, mitigate, and heal.
  • Again, Joonbob has an excellent video on how to perform this mechanic.
  • For Secundus Terminus Est, players with a cross will drop their marker at intercardinal edges, while players with a X will drop them at cardinal edges. You can stack them if two players accidentally went to the same spot, but it does extra damage, so be careful.
  • Move to the middle to dodge the sword AoEs. The middle should be completely safe, but squeeze in if someone dropped their mark closer.
  • The Tertius Terminus Est mechanic is the opposite of the previous one, so you will know which mechanic is about to occur.
  • Mitigate Divide Et Impera and DPS the boss down before it enrages.

PUG Strategy

The strategies used in pugs are exactly that detailed in this guide. For the first mechanic, some groups will do 4/4, aka having four people take east/west orbs and rotate around. I do not recommend this strat, because of the high movement requirement as well as overcomplication of the mechanic.

Role Specific Tips


  • While pulling the boss, put up mitigation with or before your opener so it covers tank busters in P1 and P2.
  • Reprisal Optimized Ultima.
  • Tank swaps are not necessary in this fight. The OT, however, should make sure to stack with the tank and mitigate all Divide et Impera busters.
  • Put up party mitigation shields for heavy raidwide damage, like for Aetheroplasm Production.
  • Take the Photon Burst away from the party.


  • Heavily mitigate Aetheroplasm Production. Make sure you have spot heals when coming in.
  • Pre-position for donut and circle AoEs to maximize casts.
  • Make sure to top players off before raidwides, as even with vuln stacks they can survive.
  • As healers are not targeted for Secundus Terminus Est, they can plant themselves in the middle.
  • Save your Surecast to get uptime if the Tertius Terminus Est is accompanied with Emerald Crush.


  • Avoid taking vuln stacks.
  • Make sure to drop your mechanics at the edge to ensure safe spaces for all players.

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