The Beheaded Knight is one half of the Haunted Duo, the pair of elite knights that guard the 
Somber Trapdoors in the Collapsed Kingdom. It fights with a greatsword and a ghostly second arm that only shows up mid-combo. It has 195 health, hits for 15 to 18 before armor, and caps every hit you land at 21, so it’s a long fight rather than a hard one.
You’ll never find one alone, as it always sleeps next to a Resurrected Knight, and the two fight as a team once they’re awake. Killing the Beheaded Knight drops the 
Somber Key Blade, which is half of the 
Somber Key that opens the trapdoor down to the Possessed Paladin. The other half comes from its partner, so you’ll have to beat both.
Location
The Beheaded Knight only spawns inside the Collapsed Kingdom, the underground ruin that generates below Forests, Birch Forests and Plains. Each kingdom holds two Haunted Duo pairs, and both are on the way to the boss. One pair sleeps in the upper halls beside the first Somber Trapdoor, and the second waits deep in the dungeon beside the trapdoor that drops into the arena.
Both trapdoors are locked, and each one eats a Somber Key when you open it, so a full run to the Possessed Paladin means killing both pairs, as there’s no digging around either hatch. Each pair sleeps beside its own trapdoor, so the two fights come one at a time.
The 
Eye Of Ghost, crafted from 
Soul Torches around an 
Ender Pearl, will point you at the nearest kingdom if you’d rather not use the command. Throw it like an Eye of Ender, follow the direction it flies, and throw again as you get closer.
The knights start asleep, kneeling in their hall, and nothing you do to them from a distance will register. They can’t be damaged, targeted or hit with effects until they wake, which happens when you come within 10 blocks. Both knights get up together, and the wake-up animation gives you a few seconds to pick your spot before the first swing.
Behavior
Awake, the Beheaded Knight is a slow, heavy melee fighter that closes the gap with short dashes before each swing. It goes after players, 
Iron Golems and 
Snow Golems, and it won’t hurt the other Collapsed Kingdom mobs, so you can’t get the Haunted Guards to thin it out for you. Every swing that connects also knocks your 
Shield out for 5 seconds.
Attacks
On its own it cycles through an uppercut, a lunging stab and two longer combos where the ghost arm appears. Most of its hits launch you into the air, and that’s what makes the combos dangerous, as the second and third swings catch you while you’re still landing. The table below has the damage before armor.
| Attack | Reach | Damage | What to Know |
|---|---|---|---|
| Uppercut | 3.5 blocks | 17 | A wide swing that launches you |
| Stab | 5.5 blocks | 17 | Dashes to where you were standing |
| Ghost Combo | 5.5 blocks | 15-17, five hits | The ghost arm appears, ends with two slams along a line |
| Ghost Uppercut | 5 blocks | 15-17, three hits | Soul Pillars come up between the slashes |
| Grab and Throw | 4 blocks on landing | 8, plus pillars | Throws the Resurrected Knight at you |
| Synergy Slam | 2.75 blocks | 15-18, five hits | Four slashes then a 360 degree slam, Shield off 7.5 seconds |
The Soul Pillars are the part people miss. During the Ghost Uppercut and the Synergy Slam the knight leaves a trail of purple pillars along its path, each one hitting for 8 ghostly damage that your armor does nothing against. Every pillar that lands also adds a stack of Soul Fracture, which takes a fifth off your maximum health for 10 seconds, and it stacks up to five.
Special Mechanics
The Haunted Duo is the mechanic that matters here. While the Resurrected Knight is within 10 blocks, the Beheaded Knight fights as a pair, and every 15 seconds or so the two line up a synergy attack. It can also grab its partner when it’s within 5 blocks and hurl it at you, and the landing does 8 damage within 4 blocks plus a ring of Soul Pillars.
Walk the Beheaded Knight more than 10 blocks from its partner and the duo logic switches off. There’s no synergy slam and no grab and throw, just the solo attack set, and that’s a fight you can win with a 
Diamond Sword and patience. The halls are long enough to do this in most kingdoms.
Like the other minibosses in Legendary Monsters, the Beheaded Knight caps every hit at 21 damage, so a huge modded weapon is wasted on it and a fast sword does about as well. It takes no damage at all while you’re 4 or more blocks above or below it, and every second hit breaks the blocks around it if mob griefing is on.
It can’t be knocked back and it’s immune to fire and fall damage. Leave it alone for a few seconds and it starts healing 20 health at a time, so backing off to eat costs you more than it saves. Stay on it once the fight starts, and eat between its combos rather than out of reach.
Drops
Every Beheaded Knight drops 1 Somber Key Blade and 1 
Metal Debris, and neither is affected by Looting. The Somber Key Blade combines with the 
Somber Key Ring from the Resurrected Knight to make the Somber Key, which is the only way to open a Somber Trapdoor. It’s one key per trapdoor, and the key’s used up when the lock breaks.
Beheaded Knight Drops
Metal Debris is the crafting material for the two knight weapons. The 
Shattered Greatsword takes 2 Metal Debris, 2 
Iron Nuggets and a 
Stick and hits for 12, slowly, and the 
Resurrected Javelin uses the same ingredients in a different layout for a 10 damage spear you can throw. Each pair of knights drops exactly 2 Metal Debris, so one weapon per pair.
There’s no experience worth mentioning and no rare drop to farm, as the knights don’t respawn once killed. Two pairs per kingdom means 2 Somber Keys and 4 Metal Debris from a full run, which is one Shattered Greatsword and one Resurrected Javelin if you’d like both.
Strategy
Bring Diamond armor at least, with Protection IV on as much of it as you can, because the pillar damage goes straight through armor points. A Diamond Sword with Sharpness V is plenty given the 21 cap, and Fire Aspect and Smite are wasted, as the knight’s immune to fire and doesn’t count as undead. Leave the Shield at home, since one hit disables it for 5 seconds.
Clear the Haunted Guards and Fractured out of the hall first, then wake the pair and back down the corridor so the Beheaded Knight follows you out of its partner’s 10 block range. Once it’s alone, stay close and to its side, hit it two or three times after each swing, and step out when the ghost arm shows, as that’s the start of a combo.
Don’t pillar up or dig down to fight it, because 4 blocks of height makes it invulnerable and it’ll break the blocks under you anyway. The corridor floor is the only place this fight happens, so clear the smaller mobs off it before you start.
If you can’t separate them, kill the Resurrected Knight first. It has slightly less health and its solo attack set is easier to read, and once it’s dead the Beheaded Knight loses the grab, the throw and the synergy slam in one go. Watch for the moment both knights stop and square up to you, as that’s the synergy wind-up, and sprint out of the slam radius.
FAQ
Only in the Collapsed Kingdom, the underground ruin under Forests, Birch Forests and Plains. There are two in each kingdom, each asleep next to a Resurrected Knight in the hall with a Somber Trapdoor, one in the upper level and one just before the Possessed Paladin‘s arena. Use /locate structure legendary_monsters:collapsed_kingdom or an Eye Of Ghost to find one.
Either it’s still asleep, or you’re too high or too low. Sleeping knights take no damage until you come within 10 blocks and wake them. Once awake, the knight ignores every hit while you’re 4 or more blocks above or below it, so a pillar or a pit does nothing, and it’ll also break the blocks around itself every second hit.
Always 1 Somber Key Blade and 1 Metal Debris. The blade plus the Somber Key Ring from the Resurrected Knight makes a Somber Key, which opens one Somber Trapdoor. Two Metal Debris, one from each knight in the pair, craft either a Shattered Greatsword or a Resurrected Javelin with 2 Iron Nuggets and a Stick.
Separate them first, because the synergy slam and the grab and throw only work while the two knights are within 10 blocks of each other, so lead one down a corridor and fight it alone. If that fails, focus the Resurrected Knight first, wear Protection IV for the armor-piercing Soul Pillars, and skip the Shield, which every hit disables for 5 seconds.
