Commander O'Neil

Commander O'Neil
Type	Great Boss
Region	Caelid
Runes	12,000
Weak To	Pierce
Required	No

Commander O'Neil is a great boss in Elden Ring.

Commander O'Neil is a rot-stricken veteran who still holds his ground in the Swamp of Aeonia in Caelid. He swings a halberd wrapped in a battle standard and calls spirit soldiers to fight beside him. He carries the Unalloyed Gold Needle that Millicent's questline needs. The whole swamp builds up scarlet rot, so fighting on Torrent is the easiest approach.

Lore

O'Neil wears the heavy armor of a battlefield commander. He carries a time-worn halberd with a beaten red battle standard furled around it.

O'Neil fought in the great battle in the Swamp of Aeonia. His lord fled, yet he went on brandishing his flag across the rot-eaten battlefield. He is the sole veteran who still remembers that battle with pride.

Where to find Commander O'Neil Location?

Swamp of Aeonia, at the heart of the rot swamp (Inner Aeonia Site of Grace)

Commander O'Neil map location:

Map credit by Map Genie.

Weaknesses

Weak To	Pierce
Resists	Slash
Immune	Scarlet Rot, Madness
Parry	Yes

Phases

Phase 1: O'Neil fights with his standard and calls a group of spirit soldiers with crossbows.
Phase 2: at half health he calls three large spirit soldiers with axes.

Attacks

Standard sweeps and thrusts: heavy halberd swings that are easy to parry.
Rot Storm: he unleashes a burst of scarlet rot around him. Riding away on Torrent avoids it.
Spirit soldier summons: crossbowmen in phase one and axe soldiers in phase two. They are quick to kill from horseback.
Rot buildup: his attacks inflict scarlet rot on hit.

Tactics

Fight on Torrent to stay out of the rot and outrun his counters.
Sneak up behind him at the start and land free hits before he summons.
Clear his spirit soldiers from horseback before focusing on him.
Summon Polyanna, Adopted Daughter from her sign near the Inner Aeonia Site of Grace, or a tanky spirit ash.
Parry his halberd attacks when fighting on foot.
Use pierce damage, because he takes extra damage from thrusting attacks.

Best Builds

Gravity sorcery from horseback

Rock Sling hits hard and can be found in the nearby ruins.

Gear	Rock Sling

Frost or bleed weapon

Frostbite and blood loss both work well on him.

Thrusting weapon on Torrent

He takes extra damage from pierce, and hit-and-run attacks avoid the rot.

Gravity Sorcerer Build

Class	Any
Level	156
Focus	Intelligence
Main Stats	Intelligence, Vigor
Other Stats	Mind, Faith
Requires	60 Intelligence, 17 Faith, 10 Dexterity, 8 Strength
Weapon	Carian Regal Scepter
Off-Hand	Meteorite Staff, Golden Order Seal
Armor	Preceptor's Big Hat, Ruler's Robe, Preceptor's Gloves, Preceptor's Trousers
Talismans	Graven-Mass Talisman, Godfrey Icon
Swap In	Blessed Blue Dew Talisman, Crusade Insignia, Ritual Sword Talisman, Magic Scorpion Charm, Dragoncrest Greatshield Talisman
Spells	Collapsing Stars, Meteorite of Astel, Gravitational Missile, Blades of Stone, Rock Sling
Flasks	Equal Charges
Crystal Tear	Magic-Shrouding Cracked Tear, Cerulean Hidden Tear
Great Rune	Radahn's Great Rune

Meteor Mage Build

Class	Any
Level	150
Focus	Intelligence
Main Stats	Intelligence
Other Stats	Vigor & Mind
Requires	60 Intelligence, 10 Dexterity, 8 Strength
Weapon	Carian Regal Scepter, Meteorite Staff, & Frenzied Flame Seal
Armor	Any Light Armor
Talismans	Ritual Sword Talisman, Magic Scorpion Charm, Godfrey Icon & Graven-Mass Talisman
Skills	Spinning Weapon
Spells	Collapsing Stars, Gravity Well, Rock Sling, Meteorite, Meteorite of Astel
Flasks	Split between HP and FP

Summons

Spirit Ashes allowed
NPC: Polyanna, Adopted Daughter

Drops

Defeating it grants 12,000 runes.

Name	Image
Commander's Standard
Unalloyed Gold Needle

Notes

The Unalloyed Gold Needle is needed by Sage Gowry to stem Millicent's rot.
He shares his armor and standard with Commander Niall of Castle Sol.

All Bosses

The table below lists all Bosses in Elden Ring.