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

DLC Bosses

Main Bosses

Optional Bosses

Mini-Bosses

Hostile NPCs and Invaders