How to Beat Commander O'Neil: Boss Fight Guide

This is a guide on how to beat Commander O'Neil, an optional boss in Elden Ring. Read on to learn more about Commander O'Neil's drops, weaknesses, and recommended level!

Commander O'Neil General Info

Stats and Rewards

Commander O'Neil
Weakness	Resistance	Immune
Magic Fire Thrust	Slash Bleed Frost Sleep Poison	Scarlet Rot Madness Instant Death
Affected By	Bleed, Frost, Poison, Sleep
Spirit Ashes Available?	Yes
Rune Rewards	12000 (NG)
Summonable NPCs	・Polyanna, Adopted Daughter
Location	・Swamp of Aeonia, Caelid
Item Drops	・Unalloyed Gold Needle

Commander O'Neil Location

Where to Find Commander O'Neil

Commander O'Neil can be found in the Swamp of Aeonia, just south of the Inner Aeonia Site of Grace. If you approach from the west, you may encounter Millicent. Instead, go around to the north of the swamp and come down, stopping at the Inner Aeonia Site of Grace on your way.

After you defeat Commander O'Neil, the Heart of Aeonia Swamp Site of Grace will appear.

When to Fight Commander O'Neil

How to Beat Commander O'Neil

Tips for Beating Commander O'Neil
Chip Away Commander O'Neil's HP from Afar
Stay on your horse for the majority of the fight
Prioritize getting rid of his summons, then deal with him

Chip Away Commander O'Neil's HP from Afar

Ranged users will have an advantage in this fight due to Commander O'Neil's slow movement speed. Try to get to the opposite side of the arena to have plenty of time to cast your spells or ranged attacks. You can even climb up on the tree roots and give yourself an extra advantage that way.

Stay on your horse for the majority of the fight

Your basic strategy for dealing with Commander O'Neil is to dash by, get in an attack before he can react, and keep circling him clockwise. He holds his Commander's Standard in his left hand, and circling him clockwise forces him to take a strong, slower swipe that you can avoid easily by sticking to his right side. Staying on horseback will allow you to outpace him for the whole fight, as his walking speed is extremely slow.

Prioritize getting rid of his summons, then deal with him

Commander O'Neil is manageable enough on his own, but he will summon a group of enemies that will complicate things if not dealt with. Equip AoE Ashes of War like Hoarfrost Stomp, or AoE spells such as Carian Slicer to wipe them out when they group up to attack you.

Commander O'Neil Attack Patterns

Spirit Summon Attacks

Spirit Summon Attack Variations
Spirit Summon: The battle starts with Commander O'Neil summoning spirit enemies. Half of them will use crossbows and stay at the edge of the arena, while the other half will carry small swords and chase after you. Lure the melee summons to where the crossbow summons are and wipe them out with wide AoE attacks. He'll summon more enemies halfway through the fight, this time with axe-wielding foes. Their attacks are slower, but they hit harder.
Spirit Buff: Commander O'Neil will shout out, buffing his summons. He can increase their attack or defense with this move.

Melee Attacks

Melee Attack Variations
Halberd Stab: Commander O'Neil's favorite attack for when you get close. It has a long reach, and if he lands the first strike, he will likely follow up with another. Avoid this attack by sticking to his right shoulder and following clockwise as he twists in an attempt to land this attack. Strike him as he's turning toward you and either dash away or continue circling him to get in another strike.
Halberd Swipe: A long-reaching horizontal attack that is often followed up with another horizontal swipe in the opposite direction. This attack covers more ground than the Halberd Stab, so you're likely to get hit if you attempt to back out of its reach. Instead, run straight ahead, sticking as close to the boss as possible, or else try to leap over the attack.
Upward Halberd Swing: This is very similar to the Halberd Stab, with an added lifting motion on the end. It's a largely ineffective attack, as the longer animation leaves Commander O'Neil open for you to run in for a side swipe.

Rot Tornado Attacks

Rot Tornado Attack Variations
Rot Tornado: Look for the white streams of wind to form around the head of Commander O'Neil's halberd for the start of this attack. He will then spin the halberd in wide circles, kicking up a large cloud of Rot-inducing dust. It's very difficult to recover from Rot in the middle of battle, so get back as far as possible when you notice Commander O'Neil starting this attack.
Small Rot Tornado: This smaller version only encompasses the area directly around Commander O'Neil, but there's a much shorter cast time, so it has the potential to catch you off guard. Just like the regular version, though, you'll get Rot if the cloud hits you.

Elden Ring Related Guides

List of All Bosses

Main Bosses

All Bosses in Elden Ring
Margit the Fell Omen	Godrick the Grafted
Red Wolf of Radagon	Rennala, Queen of the Full Moon
Royal Knight Loretta	Starscourge Radahn
Godfrey, First Elden Lord	Morgott, the Omen King
Rykard, Lord of Blasphemy	Fire Giant
Malenia, Blade of Miquella	Mohg Lord of Blood
Regal Ancestor Spirit	Astel, Naturalborn of the Void
Lichdragon Fortissax	Godskin Duo
Dragonlord Placidusax	Maliketh, the Black Blade
Sir Gideon Ofnir, the All-Knowing	Hoarah Loux, Warrior
Radagon of the Golden Order	Elden Beast

Optional Bosses

Limgrave Optional Bosses
Beastman of Farum Azula	Bloodhound Knight Darriwil
Demi-Human Chiefs	Flying Dragon Agheel
Guardian Golem	Leonine Misbegotten
Mad Pumpkin Head	Miranda the Blighted Bloom
Patches	Runebear
Scaly Misbegotten	Soldier of Godrick
Stonedigger Troll	Tree Sentinel
Liurnia of the Lakes Optional Bosses
Adan, Thief of Fire	Alabaster Lord
Alecto, Black Knife Ringleader	Bols, Carian Knight
Bloodhound Knight	Glintstone Dragon Smarag
Glintstone Dragon Adula	Magma Wyrm Makar
Royal Revenant	Spirit-Caller Snail
Caelid Optional Bosses
Battlemage Hugues	Black Blade Kindred (Caelid)
Commander O'Neil	Decaying Ekzykes
Fallingstar Beast	Flying Dragon Greyll
Frenzied Duelist	Magma Wyrm
Nox Swordstress & Nox Priest	Putrid Tree Spirit
Altus Plateau Optional Bosses
Ancient Dragon Lansseax	Crucible Knight Ordovis
Demi-Human Queen Gilika	Demi-Human Queen Maggie
Demi-Human Queen Margot	Draconic Tree Sentinel
Elemer of the Briar	Esgar, Priest of Blood
Fell Twins	Full-Grown Fallingstar Beast
Godefroy the Grafted	Kindred of Rot
Mohg, The Omen	Necromancer Garris
Onyx Lord	Perfumer Tricia
Red Wolf of the Champion	Sanguine Noble
Virgin Abductors	Wormface
Mountaintops of the Giants Optional Bosses
Astel, Stars of Darkness	Black Blade Kindred (Mountaintops of the Giants)
Borealis the Freezing Fog	Commander Niall
Misbegotten Crusader	Putrid Grave Warden Duelist
Great Wyrm Theodorix	Vyke, Knight of the Roundtable
Siofra River Optional Bosses
Ancestor Spirit	Valiant Gargoyles
Mimic Tear
Ainsel River Optional Bosses
Dragonkin Soldier of Nokstella	-
Deeproot Depths Optional Bosses
Crucible Knight Siluria	-
Multiple Location Optional Bosses
Ancient Hero of Zamor	Black Knife Assassin
Bell Bearing Hunter	Cemetery Shade
Cleanrot Knights	Crucible Knight
Crystalian	Death Rite Bird
Deathbird	Erdtree Avatar
Erdtree Burial Watchdog	Godskin Apostle
Godskin Noble	Grafted Scion
Grave Warden Duelist	Mad Pumpkin Head
Misbegotten Warrior	Night's Cavalry
Omenkiller	Tibia Mariner
Dragonkin Soldier	-

Mini-Bosses

All Bosses in Elden Ring
Elder Dragon Greyoll	Lion Guardian
Valiant Gargoyle (Leyndell)	-

Hostile NPCs and Invaders

Limgrave Invaders and Hostile NPCs
Bloody Finger Nerijus	Old Knight Istvan
Recusant Henricus	-
Liurnia of the Lakes Invaders and Hostile NPCs
Great Horned Tragoth	Festering Fingerprint Vyke
Altus Plateau Invaders and Hostile NPCs
Eleonora, Violet Bloody Finger	Inquisitor Ghiza
Maleigh Marais, Shaded Castle Castellan	Rileigh the Idle
Vargram the Raging Wolf & Errant Sorcerer Wilhelm	Magnus the Beast Claw
Mountaintops of the Giants Invaders and Hostile NPCs
Juno Hoslow, Knight of Blood	-
The Roundtable Hold Invaders and Hostile NPCs
Mad Tongue Alberich	-
Multiple Location Invaders and Hostile NPCs
Anastasia, Tarnished-Eater	-

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