Core Keeper is a mining and survival game, and its bosses are the giant creatures guarding its toughest spots. Beating one usually drops rare gear, a key item, or a piece of the story, and some unlock new areas. Some bosses are needed to finish the game, some are optional, and a few only open up after the final boss. Knowing how the fights work and which ones you can't skip makes the whole run easier to plan.
Encounter
Story
Glurch the Abominous Mass
A large slime boss found in an arena close to the Core.
- Type
- Story boss
- Location
- The Undergrounds
- Base HP
- 2,459
- Find or Summon
- Usually found in an arena about 65 tiles from the Core. Use a Giant Slime Summoning Idol at its rune to respawn it.
Ghorm the Devourer
A roaming larva boss that circles through two inner biomes.
- Type
- Story boss
- Location
- The Clay Caves and The Forgotten Ruins
- Base HP
- 8,061
- Find or Summon
- Roams a circular route through The Clay Caves and The Forgotten Ruins. Use a Ghorm Summoning Idol at its rune to respawn it.
Malugaz the Corrupted
A Caveling boss summoned at a throne-room sigil in The Forgotten Ruins.
- Type
- Story boss
- Location
- The Forgotten Ruins
- Base HP
- 14,513
- Find or Summon
- Summon it at the throne-room sigil with a Skull of the Corrupted Shaman, crafted from three Crystal Skull Shards.
Azeos the Sky Titan
A story Titan in Azeos' Wilderness; Awakened Azeos is its Easter-event form.
- Type
- Story Titan
- Location
- Azeos' Wilderness
- Base HP
- 31,813
- Find or Summon
- Use a Large Shiny Glimmering Object in Azeos' Wilderness to summon it. During the Easter event, Awakened Azeos is its seasonal form.
Omoroth the Sea Titan
A sea Titan surfaced by fishing an Expert Lure in a whirlpool.
- Type
- Story Titan
- Location
- The Sunken Sea
- Base HP
- 90,772
- Find or Summon
- Fish with an Expert Lure in one of the Sunken Sea whirlpools to summon it.
Ra-Akar the Sand Titan
A desert Titan summoned by placing a Thumper in its arena.
- Type
- Story Titan
- Location
- The Desert of Beginnings
- Base HP
- 160,799
- Find or Summon
- Place a Thumper in Ra-Akar's arena in The Desert of Beginnings.
Druidra the Wild Titan
A roaming nature Titan called with the Wind Organ of Wilderness.
- Type
- Story Titan
- Location
- Azeos' Wilderness
- Base HP
- 136,992
- Find or Summon
- Use a Wind Organ of Wilderness near its roaming path in Azeos' Wilderness. The listed HP is base health and excludes its protective shield.
Crydra the Ice Titan
A roaming ice Titan in The Sunken Sea, called with the Wind Organ of Ice.
- Type
- Story Titan
- Location
- The Sunken Sea
- Base HP
- 136,992
- Find or Summon
- Use a Wind Organ of Ice near its roaming path in The Sunken Sea. The listed HP is base health and excludes its protective shield.
Pyrdra the Fire Titan
A roaming fire Titan called with the Wind Organ of Fire.
- Type
- Story Titan
- Location
- The Desert of Beginnings
- Base HP
- 136,992
- Find or Summon
- Use a Wind Organ of Fire near its roaming path in The Desert of Beginnings. The listed HP is base health and excludes its protective shield.
Core Commander
The final story encounter at the Core, unlocked after collecting the Titan Souls.
- Type
- Final story boss
- Location
- The Core
- Base HP
- 465,385
- Find or Summon
- Activate the Crystal Meteorite after collecting all six Titan Souls. A Core Commander Summoning Idol allows a rematch.
Encounter
Post-game optional
Nimruza, Queen of the Burrowed Sands
An optional post-story boss in an Oasis dungeon, summoned with Corrupted Sap.
- Type
- Post-game boss
- Location
- Oasis, The Desert of Beginnings
- Base HP
- 228,320
- Find or Summon
- Use Corrupted Sap on the rune in her Oasis dungeon in The Desert of Beginnings.
S.A.H.A.B.A.R.
A post-story machine boss that becomes vulnerable when all four legs are disabled.
- Type
- Post-game machine boss
- Location
- Breaker's Reach
- Base HP
- 144,414
- Find or Summon
- Use Profane Override at the summoning point in its Breaker's Reach arena. Disable all four legs together to make the main body vulnerable.
Encounter
Optional
The Hive Mother
An optional Larva Hive boss; Haunted Hive Mother is its Halloween-event form.
- Type
- Optional boss
- Location
- The Larva Hive, The Clay Caves
- Base HP
- 24,671
- Find or Summon
- Found in the Larva Hive. Use a Hive Mother Summoning Idol at its rune to respawn it. Haunted Hive Mother is its Halloween-event form.
King Slime
A crossover slime boss summoned at any slime-boss rune.
- Type
- Optional boss
- Location
- Any slime-boss arena
- Base HP
- 24,188
- Find or Summon
- Use a Crown Summoning Idol at a slime-boss rune.
Ivy the Poisonous Mass
An optional poison slime boss found in Azeos' Wilderness.
- Type
- Optional slime boss
- Location
- Azeos' Wilderness
- Base HP
- 39,155
- Find or Summon
- Found in its lair in Azeos' Wilderness. Use a Giant Slime Summoning Idol at its rune to respawn it.
Morpha the Aquatic Mass
An optional aquatic slime boss in The Sunken Sea, where the arena floor is slippery.
- Type
- Optional slime boss
- Location
- The Sunken Sea
- Base HP
- 84,551
- Find or Summon
- Found in its lair in The Sunken Sea. Use a Giant Slime Summoning Idol at its rune to respawn it.
Igneous the Molten Mass
An optional molten slime boss in Molten Quarry, within The Desert of Beginnings.
- Type
- Optional slime boss
- Location
- Molten Quarry, The Desert of Beginnings
- Base HP
- 160,799
- Find or Summon
- Found in Molten Quarry. Use a Giant Slime Summoning Idol at its rune to respawn it.
Atlantean Worm
A roaming sea boss that surfaces when a Bait Pillar is placed nearby.
- Type
- Optional sea boss
- Location
- The Sunken Sea
- Base HP
- 9,641 per segment
- Find or Summon
- Roams The Sunken Sea. Place a Bait Pillar near it to bring it to the surface; the HP value is for one segment.
Urschleim
An optional slime boss that moves along a set route through The Passage.
- Type
- Optional slime boss
- Location
- The Passage
- Base HP
- 249,826
- Find or Summon
- Roams a set route through The Passage. Use a Primeval Slime Cell in the biome to respawn it.
Oblidra the Void Lord
An optional Void Titan that roams Breaker's Reach, summoned with a Wind Organ of Void.
- Type
- Optional Titan
- Location
- Breaker's Reach
- Base HP
- 160,092
- Find or Summon
- Roams Breaker's Reach. Place a Wind Organ of Void near it to summon it.
How Core Keeper Bosses Work
Bosses are much bigger and tougher than regular enemies, and they don't all fight the same way. Some wait in an arena until you summon them. Others roam the map along set routes, so you have to find them before you can fight.
Most bosses don't come back on their own after you beat them. You can bring many of them back by placing a summoning idol on their rune, the marked spot on the ground where they appear. That makes it possible to face a boss again later, which is handy once you have better gear.
Story Bosses You Need to Beat
Story bosses are the fights the main path depends on. The first three are Glurch the Abominous Mass, Ghorm the Devourer, and Malugaz the Corrupted, and they are the only real checkpoint early on. Beat all three and their drops power up The Core, which lifts The Great Wall and opens the way to the outer areas.
You can fight those three in any order, but most players start with Glurch since it's usually the first one you meet. Ghorm and Malugaz come next. The later story is built around six Titans in the outer biomes. Each Titan has to be summoned before its first fight, and once you've collected the souls from all six, you can shatter the Crystal Meteorite in the Desert of Beginnings to face the Core Commander, the final story boss.
If you're short on time, focus on the early three and the six Titans, since those are the fights the story can't skip. The Core Commander sits at the end of that path.
Optional Bosses Worth Fighting
Optional bosses aren't needed to finish the story, but many are worth the trip. The Hive Mother, King Slime, Ivy, Morpha, and Igneous are the main mid-game options. Some of their drops make later fights easier. King Slime's set of drops, for example, makes slimes and sea creatures friendly to you while you wear it.
Not every optional fight is easy. King Slime has far more health than Glurch, so many players wait for better gear before they try it. The Hive Mother is worth fighting once you can craft iron-tier gear.
Post-Game Bosses
Post-game bosses open after the Core Commander, so they're meant for players who have already finished the main story and want a bigger challenge. Nimruza, Queen of the Burrowed Sands, is in the Desert of Beginnings. S.A.H.A.B.A.R. waits in Breaker's Reach, the far northern region that Oblidra the Void Lord also roams.
Urschleim is the late-game optional fight. It roams The Passage, so you find it by exploring that area.
How to Summon Core Keeper Bosses
Most bosses are called in one of a few ways. Arena bosses appear when you place a summon item on a marked spot inside their arena, like a Skull of the Corrupted Shaman for Malugaz or a Thumper for Ra-Akar. Others need a different trigger. Omoroth is called by fishing with an Expert Lure at a whirlpool in the Sunken Sea, and Druidra, Crydra, and Pyrdra each need a Wind Organ.
Roaming bosses are harder to plan for because they keep moving. The Atlantean Worm can be lured in with a Bait Pillar placed near its path, and Ghorm follows the same loop around the Core every time, so you can wait for it on its track.
How to Beat Core Keeper Bosses
Gear decides a lot. Glurch can be handled with copper or tin armor and food buffs. Ghorm is better tackled in iron-tier gear, and Malugaz asks for scarlet-tier or better, along with a large stack of healing potions.
Before any fight, clear the arena. Ground slime slows your movement, and loose objects can get in your way. Movement speed accessories and food with a speed boost help you get out of the way of attacks.
Learn the warning signs. Glurch flashes white just before it jumps, and Malugaz marks each fire with a red circle before it lands. Those few seconds are enough to move, but only if you're watching for them.
Many bosses change when they're badly hurt. Glurch jumps faster and more often once it drops to about 30 percent health, and Malugaz heals to full and charges when its first form falls. Don't wander too far, either. Glurch and Malugaz both reset to full health if you leave their area, so stay in range and keep up the pressure.
FAQ
What do Titan souls do in Core Keeper?
Each soul gives you a power the first time you beat its Titan. You can switch those powers on or off in the Souls tab, so you decide which ones to use.
Why isn't my roaming boss showing up?
Roaming bosses keep moving on set routes, so one that isn't where you expected is probably still on its loop. Ghorm circles the Core about every four minutes, so you can wait near its track and know roughly when it will pass.
Can you trap Ghorm in Core Keeper?
Not with walls, and clearing the ground around its path won't stop it either. Spike Traps placed along its track are the safest option, but they work best alongside your own attacks, since they break quickly if they're your only source of damage.