Great Olm OSRS Guide: Hands, Head Phase and Attack Cycle

Great Olm OSRS: How the Fight Works

The Great Olm is the final boss of the Chambers of Xeric and the only room in the raid you cannot leave once you walk in. He is three targets at once: the left claw (the melee hand, 600 hitpoints), the right claw (the mage hand, 600 hitpoints) and the head (800 hitpoints), all scaled to your raid. Both claws must go down to end each phase, and the head only keeps the damage you deal in his final phase.

Every other room in the raid ends when your team decides it ends. Once you pass the mystical barrier into Olm's chamber, the room seals and the fight is to the death. There is no walking out to restock, so seats, supplies and the fire wall answer all get sorted on the near side of the barrier.

Each part has its own health pool, its own defence bonuses and its own damage rule. The left claw takes 66% less damage from anything that is not melee. The right claw takes 66% less from anything that is not magic. The head takes 66% less from anything that is not ranged, and outside the final phase it heals back whatever you land on it. A team that has not split those three jobs before the barrier wastes most of its damage.

Progress is counted in hands. When both claws are down, Olm sinks underground, drops crystals on the room and comes back up on the other side with a new power: acid, flame or crystal. Teams of one to seven get three standard phases and a head phase, and every eighth player adds another standard phase. His stats reset at the start of each phase, so a dragon warhammer special landed in phase two does nothing for phase three.

The last two phases are where raids go wrong. In the penultimate phase his head glows, every power is available at once, and the left hand gains an infinity symbol during which damage heals it. Both hands have to go down within about 30 seconds of each other or the first one comes back at full health. In the final phase he stays put, crystals fall nonstop, and damage on the head finally sticks.

Before You Walk Through the Barrier

You cannot practise Olm on his own, because you only reach him by clearing the raid. What you can control is arriving with a clear job, and knowing that the job can change between phases.

You are ready if:

• You can hold a protection prayer while reading a projectile. His magic attack is a large green orb, his ranged attack is a smaller chunk of crystal, and the head has a 1 in 5 chance of switching style every time it attacks.
• You can name a sphere by colour under pressure. Red wants Protect from Melee, green wants Protect from Missiles, purple wants Protect from Magic.
• You have a setup in the right style for the target your team gave you. One weapon pointed at all three parts loses two thirds of its damage on two of them.
• Someone calls the left hand's icons. The crystal, lightning bolt and swirl that flash above the melee hand are the only warning the three timed specials give.

Come back later if:

• You treat the head as the boss. Damage on it before the final phase heals back within a few ticks, and the raid only moves when both claws are down.
• Nobody has a fire wall answer. Being trapped between two walls costs 50 to 65 damage over five seconds, and the counter is water: a water or ice spell, Humidify, or a filled watering can.
• You rely on poison or venom for chip damage. Olm is fully resistant to both.
• Your team has no plan for a bad phase. There is no leaving, so the plan has to be about recovering inside the room.

The Chamber and Its Three Attack Zones

Olm is fought in the last chamber of the Chambers of Xeric, behind the mystical barrier. The room is split into three attack zones: left, middle and right. The head attacks the zone with the most players in it. If the zone he picks is empty, he swerves his head and skips an attack in his rotation. If someone is in the zone and he swerves anyway, nothing is skipped.

That skip is the most useful piece of geometry in the fight. A skipped standard attack gets fired on the next step on top of whatever that step does, but a skipped special is never caught up. Empty the zone at the right moment and Crystal Burst, Lightning or the teleport is gone for that cycle. The catch-up only reaches back one step, so skipping two steps in a row does not bank two attacks.

Damage steers the head as well. If the right hand takes damage within 4 ticks and Olm does not scan a player, he turns his head to the right, and the same goes for the left. Thralls and burns count, which is why some larger teams bring burning claws to keep a burn on the melee hand.

Best Gear for Great Olm: Left Claw, Right Claw and Head

Olm needs three separate setups. The Chambers of Xeric strategy page on the wiki lists weapons for each target, best first:

For the melee hand, the scythe is best and the dragon hunter lance is joint second with the Soulreaper axe. Olm has the dragon attribute, so dragonbane weapons work on every part of him: the dragon hunter lance, wand and crossbow each sit second on their target's list.

There is no suggested-levels list for Olm, and the raid lets anyone through the barrier. His combat stats and max hit scale to the players in the raid, and in most small teams they end up close to a God Wars Dungeon boss. Monster Examine works on him if you want the exact numbers for your raid.

Since 25 June 2025 every part of Olm takes 50% extra damage from earth spells, the easiest upgrade available to the mage hand. Two things that look like upgrades are not. Poison and venom are fully resisted. A dragon warhammer special only drains the part it hits, so draining the left claw does nothing for the right one or the head, and every stat resets when a new phase starts.

On the melee hand, one hit of at least 1/20 of its base health makes it clench. A clenched hand is invulnerable for about 30 seconds, and Olm cannot use Crystal Burst, Lightning or the teleport while it stays clenched; his power attacks still come. The clench stops triggering for the rest of the phase once the mage hand is down, and it does not happen at all in the penultimate phase, which is why most teams take the mage hand first. Since 7 January 2026 the burning claws special also applies burn to the melee hand.

Fire walls need water. A water spell, an ice spell, Humidify or a filled watering can each douse a segment, from inside or outside the wall. Decide who carries it before the barrier.

Inventory and Supplies

For quantities, the wiki's strategy page suggests each player in a small team brings at least one overload, one prayer enhance, 2 to 3 restores and 6 to 7 brews. Solo, a stamina potion is highly recommended. If the team is short on overloads, share the doses: Olm is generally expected to take under 10 minutes.

Prayer and Spellbook

Protection prayers cut his standard magic and ranged attacks by roughly 75 to 80%. They do not block them, so you take chip damage all fight even when you play it perfectly. Budget food for it.

Read the projectile. The magic attack is a large green orb, the ranged attack a smaller chunk of crystal, and both hit for the same. The head has a 1 in 5 chance to switch style after each attack, so there is no pattern to memorise.

Spheres work differently. Red, the sphere of aggression, wants Protect from Melee. Green, the sphere of accuracy and dexterity, wants Protect from Missiles. Purple, the sphere of magical power, wants Protect from Magic. Match the colour and the damage is prevented entirely. Get it wrong and the sphere switches your prayer off and takes half your prayer points. With nothing up, it takes about half your current Hitpoints.

Lightning ignores your prayer choice. A bolt turns off your overheads, deals moderate damage and binds you for a few seconds. The bolt rarely kills you. The standard attack that lands while you are stuck with no overhead does.

Your spellbook matters for two seats. The dragon hunter wand pick for the mage hand casts Earth Surge, which needs the standard spellbook. On Arceuus you have no water or ice spell for fire walls, so carry a filled watering can. Lunar players have Humidify, and Ancient players have ice spells.

Mechanics That Decide the Fight

Powers come from a roll. There is a 1 in 3 chance that Olm uses a phase-specific attack in place of a standard one, rising to 1 in 2 in his final phase. When the roll succeeds he tries to avoid repeating a power he has already used that phase, but he can still repeat, so a second fire wall in one phase does happen.

The specials follow a fixed twelve-step rotation: standard, empty, standard, Crystal Burst, standard, empty, standard, Lightning, standard, empty, standard, teleport, then it loops. Count it and the seedlings, the bolts and the swap stop being surprises.

Where Great Olm Fits in a Raid

Olm is always the last room of a Chambers of Xeric raid. Before him the raid draws combat rooms such as Tekton, Vasa Nistirio, Vespula, Vanguards and Muttadiles, plus puzzle rooms. Every potion you save in those rooms is one more dose you carry past his barrier.

Phase by Phase

The power phases

In every phase except the last two, Olm holds one power: acid, flame or crystal. The chatbox tells you which when he rises, and the power decides which two phase-specific attacks you will see.

Both claws have to be disabled to end the phase. The head can be hit at any time but recovers the damage within a few ticks. When both hands are down he sinks underground, drops falling crystals on the chamber, and surfaces on the other side with the next power.

His stats reset when the new phase starts. Any drain you landed is gone, so plan specials for the phase you are in.

• Acid gives Acid Spray and Acid Drip: pools at 3 to 6 damage per tick with poison, and one player leaving pools behind them.
• Flame gives Deep Burn and the fire wall: a six-hit stat drain that spreads, and 50 to 65 damage for anyone caught between two walls.
• Crystal gives falling crystals and crystal bombs: a red-aura target taking 15 to 20, and bombs that add 15 damage for every tile you did not move.

The penultimate phase

You know this phase by the green glow on his head. Every power is available to him at once, so you lose the certainty of knowing which two attacks can come.

The left hand changes too. Two attacks after the teleport it shows an infinity symbol, and for the next two of Olm's attacks every hit you land on it heals it. The melee player has to stop attacking for that window, which is harder than it sounds while the rest of the team is pushing damage.

This is also the only phase with a clock. Once a hand goes down a bar fills where it was, and if the bar fills (roughly 30 seconds) the hand comes back at full health with no extra points for hitting it again. The wiki's advice is to bring both hands to around 75 hitpoints, then take the melee hand down first and the mage hand straight after, because the melee hand's healing can waste enough seconds to let the mage hand reset.

The final stand

Once both hands are down for the last time, Olm stays on the spot and makes his final stand. Crystals fall continuously until he dies, and he keeps every power and the spheres. The teleport, Lightning and Crystal Burst are gone.

This is the phase where the head matters. The autoheal is off, so damage stays, and ranged is the only style that is not cut by 66%. The chance of a power in place of a standard attack rises from 1 in 3 to 1 in 2, and his max hit goes up slightly again.

Life Siphon only appears here. Two blue projectiles land and raise shields, and you have about 6 seconds to stand on one. Everyone off the tiles takes up to 18 damage and Olm heals for five times the total, so in a big team four players in the wrong place hand back a real chunk of his health.

Fight Strategy: Head and Hand Phases

1. 1

   Agree the three seats before the barrier:

   melee on the left claw, magic on the right claw, ranged on the head.

2. 2

   Note the power when he rises.

   Acid, flame or crystal decides which two phase-specific attacks can appear.

3. 3

   Put damage into the hands and leave the head alone.

   Anything you land on the head heals back until his final stand.

4. 4

   Count the rotation:

   standard, empty, standard, Crystal Burst, standard, empty, standard, Lightning, standard, empty, standard, teleport. Step off your seedling, get out of the lightning lines, and stand on your partner for the teleport.

5. 5

   Read every sphere by colour and match the overhead.

   Red is melee, green is missiles, purple is magic.

6. 6

   Order the hands.

   In the standard phases, clench the melee hand with a heavy hit and take the mage hand down first. In the penultimate phase there is no clench and a roughly 30 second window: bring both hands to around 75 hitpoints, then finish the melee hand and the mage hand back to back.

7. 7

   When the infinity symbol appears above the left claw, stop hitting it.

8. 8

   On the final stand, put everything ranged into the head, eat the falling crystals, and get onto a shielded tile when Life Siphon lands.

What separates fast teams from slow ones is the empty steps. Three of the twelve steps do nothing at all, and any standard step can be made to do nothing: if the zone Olm picks is empty he swerves his head and skips it. He catches up a skipped standard on the next step, but never a special, so a skip timed onto Crystal Burst, Lightning or the teleport removes that special for the cycle.

Keep the two claws close together. The phase does not end until both are down, so if one hand dies in fifteen seconds and the other takes ninety, the team spent seventy-five seconds eating spheres, lightning and powers for no progress. Take the mage hand first while the melee hand is clenched, and do not let the melee hand fall far behind once the clench ends.

Positioning and Movement

Olm attacks the zone holding the most players, so where your team stands decides who gets shot. A team that drifts into one column shares every standard attack.

Crystal bombs are pure distance. The minimum hit is 15 and it climbs by 15 for every tile closer you are, over a four-tile radius, so two or three early steps turn a big hit into a small one.

The fire wall works the other way. Olm needs a certain amount of room to place it, and if players stand in the wrong spots the attack fails: he does nothing, carries on through his rotation as if it had worked, and gets no catch-up attack.

In the last phase the floor is the problem. Crystals never stop falling, acid pools from an earlier power can still be on the ground, and Life Siphon wants you on one of two tiles within about 6 seconds. Know where your clear ground is before you need it.

Beginner Plan, Then the Advanced One

Your first trips

1. 1

   Ask for the ranged seat on the head if the team will give it to you.

   It has the fewest decisions: one target, one style, and you help the hands until the final stand.

2. 2

   Learn the three sphere colours until they are reflex.

   It is the one mechanic that costs your prayer as well as your health, and it shows up in every phase.

3. 3

   Watch the left claw, not the head.

   The crystal, the lightning bolt and the swirl all appear there, and they are the only warning the three specials give.

4. 4

   Leave the head alone in the early phases.

   The autoheal takes it all back, and that time was time the hands were not taking damage.

5. 5

   When the infinity symbol appears above the melee hand, stop attacking.

   Doing nothing for two attacks beats healing it.

6. 6

   Accept the falling crystals as damage you will take.

   The teleport is different: stand on your partner when the swirl shows and it costs nothing.

Once the kill is boring

• Use the zone skip on purpose. Emptying the zone Olm has picked skips a standard attack, and because specials are never caught up, a skip on Crystal Burst, Lightning or the teleport deletes it.
• Time defence drains to the phase. A dragon warhammer special only affects the part it lands on, and all his stats reset when a phase begins, so a drain on the mage hand at the end of a phase buys nothing.
• On the mage hand, cast earth spells. The 50% weakness has been live since June 2025, and the dragon hunter wand with Earth Surge and a tome of earth is second on the wiki's list.
• On the melee hand, open with a big hit. A clenched hand is invulnerable for about 30 seconds, and Olm cannot use Crystal Burst, Lightning or the teleport while it stays clenched. The clench stops triggering for the rest of the phase once the mage hand is down. Since January 2026 the burning claws special also applies burn to it.
• Rehearse the penultimate phase. Both hands to around 75 hitpoints, melee hand down, mage hand down straight after. The window is roughly 30 seconds, and missing it restores the hand to full.
• Solo, learn the hit-to-attack ratios. The wiki's starting methods are 3:0, three hits with none taken using a 4-tick weapon such as a powered staff, and 4:1, four hits for each Olm attack using a 4-tick melee weapon such as the dragon hunter lance. A 5-tick scythe turns 4:1 into 3:1.

Team Roles

Team size changes this fight more than gear does. Olm's combat stats, max hit and health all scale to the players in the raid, and every eighth player adds a whole standard phase. A mass raid is a longer fight, and a team that clears Olm comfortably in a five-man can find a solo hard.

Some mechanics get easier in small teams and some get harder. Crystal bombs cap at three, or two in smaller groups, and Acid Drip barely matters with nobody nearby to trail pools into. The teleport goes the other way: solo, Olm picks any tile up to ten tiles from you, while in a group he pairs players up and leaves one out when the number is odd.

Stat drains do not pool across targets either. A dragon warhammer special only affects the part it landed on, so three people draining three different parts get three separate effects, each gone at the next phase.

Drops and What Great Olm Is Worth

Olm drops nothing himself. The loot is in the Ancient chest behind him, which holds the raid's unique table: the twisted bow, elder maul, kodai insignia and dragon claws are all on it. In the lore, those uniques are the weapons and armour Xeric sealed away after his party defeated Olm.

Combat Achievements

Olm's two Master tasks are Perfect Olm (Solo) and Perfect Olm (Trio). Both ask you to kill him without taking damage from teleport portals, fire walls, healing pools, crystal bombs, Crystal Burst or prayer orbs, without letting his claws regenerate, and without taking damage from the same acid pool twice in a row. The claw rule is about phase 3: let a downed hand refill its bar and the task fails.

Some things do not fail it. Dying to a standard attack is allowed, and the wiki's task pages say getting hit by Lightning or by the falling crystals does not disqualify you either.

For the solo version, the wiki leans on the safespots that force his head to turn, plus a clean 4:1 with a 4-tick weapon or 3:1 with a 5-tick weapon on the melee hand, which avoids everything except fire walls and acid. The slower 1:0 method means Olm never gets to attack you at all. Fire walls and teleport portals are the biggest threats, and an Arceuus player needs a water source such as a watering can. In phase 4 the teleport is gone, but fire walls and acid pools are not.

The trio version counts raid scale, so the wiki notes you can attempt it solo at scaling 2 or as a duo at scaling 1. In a real trio, acid trails are the most likely failure: when Olm looks at you during the acid phase and the head phase, start walking and do not attack until he turns away.

Combat Achievements guide

Ironman Notes

Without a Grand Exchange, the twisted bow, elder maul and kodai insignia only come from the Chambers of Xeric chest, so every one of them goes through Olm.

The bottom of each wiki list is reachable without raid uniques: abyssal whip or Zamorakian hasta on the left claw, trident of the seas on the right claw, and rune crossbow or Eclipse atlatl on the head. The two cheapest upgrades are earth spells for the 50% weakness and any dragon hunter weapon you own, since Olm has the dragon attribute.

The fire wall answer costs almost nothing. A filled watering can douses a segment as well as a water spell or Humidify does, which matters most if you play on the Arceuus spellbook.

Skip poisoned weapons and keep the antipoison. Olm resists poison and venom completely, but his acid pools and Olm himself can poison you.

Common Mistakes and Death Causes

There is no recovery in the usual sense. Once the team passes the mystical barrier the chamber is sealed, so every plan is a plan for carrying on.

If a phase goes badly, stop pushing damage into whatever is healing (the head outside the final stand, or the left claw while its infinity symbol is up) and spend the time restoring prayer and Hitpoints. His stats reset at the start of each phase anyway, so a slow, clean transition beats a fast, messy one.

FAQ

Still stuck on a mechanic? Ask the team on our Discord, it is free.