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Ambuscade V1: Corse Strategy
Posted 12 Feb 2022 / Updated 12 Feb 2033

Here's a strategy for the Corse Intense Ambusade.

This is all for the Very Difficult setting.
On other settings, the behaviour and number of enemies will vary, but you can still use this as a reference.

* Contents

Monster Properties
- All Monsters
- Bozzeto Pishogue x1
- Bozzeto Warder x4
Strategy Summary
Composition and Breakdown
Strategy Step by Step
Getting the KI
Video

* Monster Properties

[All Monsters]

Mewing resistance: -90%
AOE damage resistance: -95%
Slashing: -12.5%
Piercing: -50%
Blunt: +25%

Debuffs other than sleep and petrify generally apply.
Dispel/Finale doesn't seem to work?

[Bozzeto Pishogue x1]

Repeat BP wall: -90%
Geomancy resistance: -50%
Def down resistance: -30%

The Corse who acts as the boss.
Hybrid DRK/BLM.
Uses Blood Weapon at around 25% HP.
When Blood Weapon is used, all enemy debuffs are removed.
Damage taken and damage dealt both increase during Blood Weapon.
If Blood Weapon is used while adds are out, the Corse also uses Souleater at the same time.
While adds are out, Gambol Macabre becomes available as a TP move.
If the player with enmity is distant from the Corse, it will prioritise Memento Mori -> Elemental Magic.
If the player with enmity is 10 or more metres away from the Corse, it will use Gambol Macabre regardless of whether adds are out or not.

Quelling Seal: AOE silence + Paralyze
Gambol Macabre: Single-target charm and doom (both about 30 sec duration)
Hecatomb Macabre: Charms everyone but one person in range (charms everyone if the person with enmity looks away) and doom.
Charmed players receive bonus of Regen, Refresh, Regain, 9999 attack and 9999 defense.

At ~90% and ~30% HP, "A mystical veil envelops your foe" will appear in the chat log, and the Corse will summon four skeleton adds. (They won't be resummoned if there are still skeletons up.)
The skeletons will use TP moves to make skillchains that the boss will quickly magic burst.
Each skeleton gives the boss damage absorption for two elements (fire and light, earth and darkness, wind and lightning, ice and water).
Defeating skeletons makes "You sense a weakness in the mystical veil" appear in the chat log and removes one of the above damage absorption effects.
Defeating all skeletons makes "The mystical veil dissipates" appear in the chat log and removes all of the above damage absoprtion effects.

[Bozzeto Warder x4]

Geomancy resistance: -100%

Club-wielding skeletons who act as the adds.
They have Regain.
Four appear at once and inherit hate from the boss while also shuffling the hate list to each target different players.
Makes light skillchains with Dark Holy Cloud -> Dark Holy Cloud.
Makes dark skillchains with Black Cloud -> Black Cloud.

Dark Holy Cloud: Single-target damage, strong Slow, Def down, Meva down (can hit outside of melee range)

* Strategy Summary
Take out the adds before working on the boss.
Make everyone eat Hecatomb Macabre and take advantage of the hate reset and buffs it applies.

* Composition and Breakdown
PLD, DD x2, COR, BRD, GEO

[General]
When attacking the boss, make sure the DDs, COR, BRD, and GEO are all facing it.
When the Hecatomb Macabre charm wears off, slam your Holy Water macro to cleanse Doom. Nicander's Necklace and Blenmot Rings are recommended for this.

[PLD]
Shield Barrier Protect V/Holy Circle

The PLD holds hate on everything and handles curing. Aegis or Srivatsa recommended.
Back-tanks the boss from start to finish.

When first wave of adds appear:
Sub RUN Vallation + Valiance + Pflug to get hate

When second wave of adds appear:
Sentinel + Rampart + Palisade to get hate
When boss uses Souleater/Bloodweapon, dispel with Shield Bash (needs relic hands)

[DD x2]
Any job is fine as long as it can do enough damage. WAR, MNK, DRK, SAM, DRG, etc.
You need 1384 accuracy like usual, but note that accuracy will be dramatically reduced while blind [Alseyn note: from Black Cloud probably].

When adds appear, stop hitting the boss immediately and switch to taking them out.
Resume attacking the boss when all adds are down.
Follow these two rules and skillchains on the adds or the boss won't be a problem.

You could even have a DD WHM in this slot.
Maybe you won't need Holy Water gear for Hecatomb Macabre if they have a good Cursna set and AOE Cursna?

[COR]
Chaos/Samurai rolls

After rolling, DD following the instructions above.

[BRD]
Party: Honor March/Victory March
DDs/COR/BRD: Blade Madrigal/Dirge
PLD/GEO: Ballad 3/Lightning Carol

After buffing, DD following the instructions above.

[GEO]
Indi-Barrier/Geo-Fury/Entrust Haste

Sub WHM and help with heals. If ML30 or higher, apply Auspice.
If you have DD gear, feel free to bonk.

Indi-Barrier and Geo-Fury are insurance for until you get the charm bonus from Heactomb Macabre, while Entrust Haste is insurance for if you get hit with a strong Slow.
So these are all for insurance, really, but they're essential for keeping things stable while you handle the mechanics.

* Strategy Step by Step
1. After buffing, attack the boss until it hits ~90% HP and summons adds
2. Take out the adds and resume attacking the boss
3. Take the boss down to ~30% HP and spawn the second set of adds
4. Take out the adds and defeat the boss

NB: It'll make the fight take a bit longer, but if you have only one person on the boss before step 3, it'll be easier to prevent triggering Soul Eater/Blood Weapon.

* Getting the KI
Xarcabard [S] HP 1, Fei'Yin HP 1, etc.

* Video
https://www.youtube.com/watch?v=A3dn7Z4SwKQ