The Collapsed Kingdom is the Legendary Monsters dungeon that holds the Possessed Paladin, a buried ruin of halls, pits and trap corridors that starts at a surface gatehouse and runs down to a boss arena far below. It’s the mod’s biggest structure, and every knight in it is placed rather than spawned, so what you find is the whole garrison and none of it comes back.
You come here for the 
Somber Keys that its two elite knight pairs drop, for the 
Soul Great Sword the Paladin leaves behind, and for the 
Corrupted Soul that makes a knight companion of your own. It’s a mid to late game trip, and the boss at the bottom is the hardest fight the mod has.
Finding the Structure
The Collapsed Kingdom generates under Forests, Birch Forests, Old Growth Birch Forests and Plains, with a few Biomes O’ Plenty and Oh The Biomes We’ve Gone biomes added if those are installed.
Kingdoms sit well over a thousand blocks apart, so you won’t trip over one by accident, but the gatehouse pokes out of the ground and it’s easy to spot once you’re in the right area.
Without cheats, the 
Eye Of Ghost does the searching for you. It’s crafted from 4 
Soul Torches around an 
Ender Pearl and thrown like an 
Eye of Ender, and it flies toward the nearest kingdom within 100 chunks.
Throw it, follow the direction it flies, and throw again as you get closer. Walking into the ruin gives you the Locate The Collapsed Kingdom advancement, so that’s how you know you’ve got the right place before you’ve met a single mob.
The gatehouse is a tall, narrow tower of 
Stone Bricks, 
Deepslate and 
Blackstone with Stained Glass windows and 
Sea Lanterns, sitting on the surface. Everything else is underground, and the way down is inside the tower rather than around it. There’s no digging your own route either, as the rooms below are shelled in unbreakable blocks.
Layout
Every Collapsed Kingdom is built the same way, only rotated, because each section of it comes from a single fixed piece rather than a pool of options. The gatehouse leads into an upper hall and then a great tower, the largest room in the ruin, which holds the first Haunted Duo and the first 
Somber Trapdoor over a pit shaft. The pits drop you into the dungeon proper.
The dungeon is a run of Stone Brick rooms and corridors branching off a central hall. A few branches are side rooms full of Fractured and Haunted footmen, one’s a long trap corridor, and one leads to a second hall with the second Haunted Duo and the second Somber Trapdoor. That hatch opens over a short drop into the arena where the Possessed Paladin sleeps.
The corridors carry Big Spike Traps that do 12 impale damage when you stand on them, Small Spike Traps that do 8, and 
Swinging Axes on chains that hit for 13. One corridor has a long row of axes back to back. Walk rather than sprint, watch the floor, and time the axes instead of tanking them, as they hurt more than most of the mobs do.
Both Somber Trapdoors are locked, and each one eats a Somber Key when you right-click its middle. So a full run needs two keys, one from each Haunted Duo pair, and there’s no way around either hatch. 
Chests, 
Barrels and 
Decorated Pots are spread through every level, and every room past the tower sits inside a shell of 
Indestructible Block that no tool or explosion can break.
Mobs
Nothing spawns inside the kingdom over time, so the mobs you meet are the ones the structure placed and every kill is permanent. The two foot soldiers are the Haunted Knight and the Haunted Guard, both on 50 health, backed by the Fractured and the Fractured Apostle. Above them sit two Haunted Duo pairs and the Possessed Paladin itself.
| Mob | Health | Damage | What to Know |
|---|---|---|---|
| Haunted Knight | 50 | Sword combos | Parries a hit and counters with a short stun, drops a Knight’s Sword Blade Half |
| Haunted Guard | 50 | 14 | Heavy line smash that launches you, immune to Arrows, drops a Long Stick Half |
| Fractured | 40 | 15 | Slow sweep, drops nothing |
| Fractured Apostle | 50 | 4 daggers, 14 knife | Homing daggers that ignore armor |
| Beheaded Knight | 195 | 15-18 | Half of the Haunted Duo, drops the Somber Key Blade |
| Resurrected Knight | 190 | 13-15 | The other half, drops the Somber Key Ring |
| Possessed Paladin | 400 | 15-25 | The boss, asleep in the arena until you right-click it |
The Haunted Duo is the pair to read up on before you go, as the two knights fight together while they’re within 10 blocks of each other, with a synergy slam and a grab and throw that only exist as a pair. They cap your hits at 21 and sleep until you come close. Split them or kill the Resurrected Knight first, and their own pages cover the rest.
Haunted Duo Drops
The footmen are worth killing rather than running past, as their drops build two weapons. Two Knight’s Sword Blade Halves and a 
Stick make the 
Knight’s Sword, and two Long Stick Halves with a Gold Block and 3 
Gold Ingots make the 
Golden Halberd.
Those two weapons are also the tops of the 
Knight Summoner and 
Guard Summoner recipes, so hang on to one of each if you’re planning on a companion later. A spare blade half isn’t wasted either, as it turns back into an 
Iron Ingot on its own in the grid.
Loot
The Chests come in two grades, and it helps to know which is which. Basic Chests roll 
Bones, 
Bone Meal, 
String, 
Iron Nuggets, Iron and Gold Ingots, and a piece or two of Iron or Chainmail gear. Luxury Chests carry 
Diamonds, Bottles o’ Enchanting, 
Golden Carrots, Books, 
Diamond Helmets and Boots, 
Enchanted Golden Apples and the Possessed Paladin Music Disc.
Luxury Chest Highlights
Diamond 
Bottle o' Enchanting 
Golden Carrot 
Golden Apple 
Enchanted Golden Apple 
Music Disc The mob drops are the real reason to come, though. Each Haunted Duo knight drops a Somber Key half and 1 
Metal Debris, and 2 Metal Debris with 2 Iron Nuggets and a Stick makes either the 
Shattered Greatsword, a 12 damage blade, or the 
Resurrected Javelin, a throwable spear.
Two pairs per kingdom means two keys and enough debris for both weapons, so there’s no need to pick between them. The Javelin can be thrown and comes back with Loyalty, while the Greatsword reaches a block further than a normal sword.
Combine a 
Somber Key Blade and a 
Somber Key Ring to make one key. Each trapdoor eats a key when it opens, so you’ll need two per kingdom, and that means killing both Haunted Duo pairs.
Two Metal Debris, two Iron Nuggets and a Stick forge this heavy blade. It hits for 12 and swings once a second, so time each swing rather than clicking, and it’ll outdamage most swords you can craft this early.
The boss drops a Corrupted Soul, which crafts the Guard and Knight Summoners. Each one raises a loyal knight that fights beside you, and there’s only one Soul per kingdom, so you’ll have to pick.
The Corrupted Soul from the Possessed Paladin is the rare one, as it’s the center of both summoner recipes and there’s exactly one per kingdom. The Soul Great Sword drops alongside it, and that’s the strongest sword in the mod, with the boss’s own parry built in.
The Boss
The Possessed Paladin sleeps in the arena under the second trapdoor, with three Haunted Guards, two Fractured Apostles, a Haunted Knight and a Fractured for company. It won’t wake on its own and nothing damages it while it sleeps, so clear the arena first and right-click it when you’re ready. It then stands and talks for about 10 seconds before the fight starts.
It has 400 health, caps every hit you land at 21, halves any hit that lands within a second and a half of the last one, and parries you if you swing while it stands idle. Below 65% health it becomes Orion, The Fractured Omen, with a Soul Trident and a long finisher combo. Its own page covers every attack, so read it before you drop in.
Possessed Paladin Drops
Every hit it lands stacks Soul Fracture, which takes a fifth off your maximum health per stack and strips Absorption, so 
Milk Buckets matter more than Golden Apples here. It drops 1 Soul Great Sword and 1 Corrupted Soul every time, and it doesn’t come back once it’s dead.
Exploration & Strategy
The kingdom has an order to it, and doing things out of order costs you keys and lives. The steps below follow the structure from the gatehouse down, and nothing in it can be skipped, as the walls can’t be mined and both trapdoors need a key. The side rooms are the only part you’re free to leave for later.
Clear the Gatehouse and Tower
Footmen first, then the first duo
Work through the Haunted Knights and Guards in the upper halls, then wake the first Haunted Duo in the tower and separate them if the room allows. Their two key halves make your first Somber Key at any 
Crafting Table, or right in your inventory grid.
Their Metal Debris is your first weapon, so craft the Greatsword or the Javelin before going any deeper. The dungeon below is where the traps and the bigger rooms start, and a better weapon pays for itself down there.
Open the First Trapdoor
One key, right-click the middle
The first Somber Trapdoor covers the pit shaft. Right-click its center with the key, then drop down the pits with a 
Water Bucket or a stack of blocks to break the fall, and you’re in the dungeon.
Clear the Dungeon Rooms
Traps, pots and the second pair
Take the side rooms one at a time, kill the Fractured Apostles before the melee mobs, and walk the trap corridor rather than running it. The second Haunted Duo waits in the far hall with the second trapdoor, and the same split-or-focus rule applies there.
Set a Spawn and Drop In
Bed at the gatehouse, blocks over the hatch
Place a bed at the surface before the boss, because a death in the arena is a long walk back through empty halls. Bridge the second hatch with blocks if you’d rather drop in on your own terms than fall straight through into the fight.
Wake the Paladin
Arena clear, Milk in hand
Kill the arena’s Guards and Apostles, eat, then right-click the Possessed Paladin. Keep two Milk Buckets for Soul Fracture, never swing while it waits, and finish the fight in one go, because it heals and drops back to its first phase if you leave.
Leave the 
Bow at home, as the Haunted Guards, the Haunted Duo knights and the Paladin all ignore or punish ranged attacks, and bring a slow, heavy sword rather than a fast one for the capped fights. A 
Shield is handy against the footmen and does nothing against the knights, which disable it on every hit.
FAQ
Under Forests, Birch Forests, Old Growth Birch Forests and Plains, with a stone and Deepslate gatehouse on the surface marking the way in. Use /locate structure legendary_monsters:collapsed_kingdom with cheats on, or craft an Eye Of Ghost from 4 Soul Torches around an Ender Pearl and throw it, and it flies toward the nearest kingdom within 100 chunks.
Two, because there are two Somber Trapdoors on the way to the arena, one in the tower and one in the deep dungeon, and each one uses up a key when you open it. Each Haunted Duo pair drops the two halves for one key, and there’s a pair beside each trapdoor, so you’ll have to kill both pairs, as the shafts under the hatches are lined with unbreakable blocks.
It has 400, and it caps every hit you land at 21 and halves hits that come too quickly, so the fight’s long by design. It switches to its Orion phase below 65% health. Wake it by right-clicking, as it sleeps in the arena and doesn’t take any damage until then.
Not usefully, as the Haunted Guards and the Possessed Paladin ignore 
Arrows outright, the Haunted Duo knights take nothing while you’re 4 blocks above or below them, and the Resurrected Knight throws armor-piercing javelins at anyone who stands back. The Fractured Apostles are the one target Arrows are good for.
