O4S – Exdeath / Neo Exdeath

Encounter Overview

O4S is a two-phase savage encounter that begins with Exdeath and transitions into Neo Exdeath after a successful first phase clear. The fight evolves from structured mechanic execution into one of the most chaotic multi-debuff encounters in Stormblood.

The first phase focuses on layered spell combinations and positioning discipline, while the second phase introduces heavy debuff management, forced movement, and complex resolution sequences such as Grand Cross variants.

Execution consistency, role assignment, and awareness of overlapping mechanics define this encounter. Mistakes compound quickly, especially during Neo Exdeath where multiple mechanics resolve simultaneously.

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Relic Weapons Relic Armor

For a full breakdown of raid difficulty across all tiers, see the FFXIV Raid Rankings.

Arena Overview

The encounter takes place on a circular platform with no barriers. Knockbacks and forced movement mechanics are constant threats throughout both phases.

During the Neo Exdeath phase, arena pressure increases through repeated knockbacks, directional mechanics, and positioning requirements tied to debuffs and shared damage.

Boss Mechanics

Exdeath

Dualcast

Causes the next ability to resolve twice. Players must anticipate back-to-back mechanics rather than reacting to a single instance.

Fire III

Targets players with AoE markers in sequence. The raid must spread cleanly without overlapping damage.

Blizzard III

Places ground AoEs twice in succession. Players should briefly stack to bait and then move out to safe zones.

Thunder III

A double-hit tankbuster that requires either a tank swap between hits or heavy mitigation planning.

White Hole

Checks raid HP. Players not at full health are penalized heavily or killed. Healers must fully stabilize the raid before resolution.

The Decisive Battle

A transition mechanic involving tentacles and a central structure. The group moves together to avoid incoming damage and then repositions behind the structure to avoid the follow-up.

Vacuum Wave

Strong knockback that must be mitigated or positioned around. Often paired with mechanics that require players to remain grouped afterward.

Black Hole

Creates persistent hazards that must be kited by assigned players while the rest of the raid resolves other mechanics.

Flare / Holy

Spread and stack mechanics that frequently overlap with movement and positioning checks, requiring quick recognition and spacing control.

Meteor

Heavy raid damage that requires mitigation and healing coordination to survive.

Neo Exdeath

Almagest

A heavy raid-wide attack followed by a strong damage-over-time effect. Requires full mitigation and sustained healing to stabilize.

Aero III

A single-target tankbuster that requires mitigation but does not cleave the raid.

Delta Attack

A combination of Fire, Blizzard, and Thunder resolving together. Players must spread, avoid AoEs, and handle tank damage simultaneously.

Flood of Naught

A recurring mechanic with multiple variations, including directional beams, stack checks, and color-based positioning. Each version requires different positioning logic.

Grand Cross Alpha

Applies multiple debuffs including forced movement and delayed damage effects. Players must pre-position to resolve movement while avoiding additional penalties.

Grand Cross Delta

A complex debuff sequence involving stack markers, spreads, gaze mechanics, and conditional damage checks. Proper assignment and positioning are required to resolve safely.

Grand Cross Omega

A final layered debuff sequence that combines forced movement, stacking, spreads, and multiple Flood of Naught variations in rapid succession.

Double Attack

A heavy tank mechanic that either requires shared damage between tanks or invulnerability usage.

Earth Shaker

Targets players with heavy physical damage that must be directed away from the group.

Light and Darkness

Combines stack and spread mechanics with positional requirements, often followed by additional movement checks.

Charybdis

Reduces all players to critical HP, requiring immediate healing before follow-up damage.

Neverwhere

Soft enrage phase where the boss gains increasing damage over time, eventually overwhelming the raid.

Encounter Flow

The fight begins with Exdeath, establishing core mechanics through Dualcast combinations and raid-wide checks like White Hole. Players must quickly adapt to handling multiple mechanics in sequence rather than individually.

Midway through the fight, The Decisive Battle introduces transition mechanics that require coordinated movement and positioning. Following this, the encounter escalates with knockbacks, spread mechanics, and environmental hazards.

After defeating Exdeath, the fight transitions into Neo Exdeath, resetting aggro and introducing a significantly more complex phase :contentReference

Neo Exdeath focuses heavily on debuff management and overlapping mechanics. Sequences like Grand Cross Alpha, Delta, and Omega require precise positioning, timing, and awareness of multiple simultaneous conditions.

As the fight progresses, the encounter shifts into a soft enrage through Neverwhere, increasing incoming damage until the raid is overwhelmed if the boss is not defeated in time.

O4S is a defining Stormblood savage encounter, combining structured mechanics in the first phase with chaotic, high-pressure execution in the second.