The Ancient Tower Remains is the Legendary Monsters structure you’ll run into in the End, a collapsed 
End Stone tower with 
Chorus Plants grown over the whole thing. There’s a Chorusent asleep at the base of it and Choruslings spawning in around it.
What you’re really there for is the 
Chorus Crystal that the Chorusent drops, as that single item gates the 
Chorus Blade, the 
Chorus Mask and the 
Chorus Cannon. There’s also one patch of 
Suspicious Sand buried in the ruin, and that’s the only place in the mod a Void Gem will ever turn up.
Finding the Structure
The tower generates on the surface of the End islands, in End Highlands and End Midlands, and it’ll also use a few BetterEnd biomes if you have that installed. They sit about 65 chunks apart, about as rare as the Shulker Tower and not something you’ll stumble across by accident.
Bring an 
Elytra along either way, since the islands out there are broken up by long stretches of open air and flying across beats trying to bridge every gap by hand. You’ll be crossing a lot of them before the tower shows up.
Instead of sweeping the End, craft an 
Eye Of Chorus from 4 
Chorus Fruit around an 
Ender Pearl. Throw it and it flies toward the nearest tower within 100 chunks, just like an 
Eye of Ender, usually dropping back down for you to pick up. It still works as a normal Eye of Ender as well, so a spare one will fill an 
End Portal Frame.
If you’d rather skip the crafting, the structure has an id you can feed straight to the locate command. It’ll point at the closest one from wherever you’re standing in the End.
The command gives you coordinates rather than a direction, so it pairs well with an Elytra. Fly straight there and you’ll usually spot the Chorus Plants growing over the ruin before you make out the tower itself.
Layout
The ruin is built from End Stone and 
End Stone Bricks with 
Purpur Blocks and 
Purpur Pillars through it. 
End Rods light the inside, 
Magenta Stained Glass is set through it, and Chorus Plants and 
Chorus Flowers have grown over most of the broken sections. Nothing in it is sealed, and there are no doors or locked rooms.
Almost everything worth having sits at ground level. Three Chorusling spawners are spread around the base, two 
Shulker Boxes are down there as well, and a single block of Suspicious Sand is down there with them. The Chorusent itself is asleep in the middle of the floor, so you’ll be dealing with the spawners and the boss in the same open space.
The third Shulker Box is the one people miss, as it’s set roughly halfway up the tower instead of on the floor with the others. There are no 
Ladders anywhere in the ruin, so bring blocks or an Ender Pearl if you want it. No traps are built into the structure at all, the only thing that will hurt you is what lives in it.
Mobs
Only two kinds of mob live here, and they’re both from the same Chorus family, one big and slow to wake, the other small and constant. 
Arrows do nothing to either of them, which is the detail that decides how the whole visit goes.
Chorusent
Chorusling
The Chorusent is the one asleep on the floor, standing 6 blocks tall once it gets up, and it has its own article covering the fight properly. It’s slow on its feet but it blinks around constantly, and it will not take a single point of damage until it has finished waking.
Choruslings are the small ones, and the three spawners keep making them the whole time you’re inside, a few at a time every 10 to 40 seconds. They hit for 5 and put Chorus Infection on you with every landed hit, which chips 3 damage at a time and hops you a couple of blocks.
Raising a 
Shield stops the infection going on you, though a Chorusling will knock that Shield out of your hands for 2 seconds when it connects. They’re immune to Arrows as well, so there’s no shooting them off the spawner from a safe corner. Choruslings also spawn on their own across End Highlands, End Midlands and Small End Islands, so you might meet a few on the way in.
Loot
Two of the three Shulker Boxes are filled and the third generates empty. The empty one’s on the ground floor, so the box set high up is always worth the climb. Each filled box rolls the End City Treasure table between 2 and 6 times, so it’s the same pool you’d get out of an End City, and the boxes themselves can be mined and carried off.
Shulker Box Loot
Gold Ingot 
Iron Ingot 
Smithing Template 
Diamond 
Beetroot Seeds 
Saddle 
Diamond Sword 
Diamond Chestplate 
Diamond Pickaxe 
Iron Sword 
Emerald 
Diamond Horse Armor Every Diamond and Iron tool or armor piece in that table sits on the same 3.5% and arrives enchanted at 20 to 39 levels, so the Iron pieces are often worth more for the Books on them than the gear itself. The Spire Armor Trim Smithing Template comes from a separate roll made once per box.
The Suspicious Sand is the part that makes the trip worth repeating. Brushing it gives a Void Gem, and there is exactly one block of it per tower, with no other source anywhere in the mod. The Void Sword needs 2 Void Gems and a 
Withered Bone from the Withered Abomination, so one sword means clearing two separate towers.
Killing the Chorusent gives 1 Chorus Crystal and 40 experience, and the Choruslings hand over 1 to 3 
Infected Chorus Fruit each. Between them those two drops open up everything the location is here to unlock.
- Chorus Blade, made from a Chorus Crystal, an Iron Sword and 2 Infected Chorus Fruit, which teleports you a short way on right-click
- Chorus Mask, which takes a Chorus Crystal, 4 Chorus Fruit and 1 Infected Chorus Fruit, and strips Chorus Infection off you while it’s worn
- Chorus Cannon, needing a Chorus Crystal, a Sand Cannon, a Gold Ingot and 2 Infected Chorus Fruit
- Void Sword from 2 Void Gems and a Withered Bone, at 10 attack damage and 250 durability
- Void Entity Warper, which surrounds an Entity Warper with 8 Infected Chorus Fruit
The recipes below cover the three Chorus items, and the Void Sword has a page of its own. Between the crystal and the fruit, the tower is where all of them start.
Only one Chorus Crystal drops per Chorusent, and each of those three crafts eats a whole crystal. Getting all of them means finding three towers, which is the real reason you’ll end up throwing more than one Eye Of Chorus.
The Boss
There’s no summoning block and no item to place here, as the Chorusent is simply lying there asleep when the tower generates. It never despawns either, so a tower you’ve found and left alone will still have its boss waiting when you come back.
It wakes when a player gets within 15 blocks of it with line of sight, and the wake animation runs for about a second. Nothing you do lands during that second, as it’s flatly immune to damage and to potion effects until it’s fully up.
Any projectile that hits the Chorusent deals zero damage and teleports it up to 7 blocks away instead. Arrows, 
Tridents, 
Snowballs and thrown Potions all count, so a 
Bow is worse than useless here, it just moves the fight around. Bring a melee weapon and plan on closing the distance.
It has 200 health and 10 armor and can’t be knocked back. Up close it smashes with one arm for 12 or both for 15, reaching about 7 blocks in front of it, and it blinks away right after each hit, so trading hits in one spot never works.
From up to about 12 blocks out it uses a teleport strike instead, marking where you stand and arriving a second later, so walking after the wind-up makes it land on empty floor. That one is on an 8 second cooldown, whereas the arm smashes come back in around 3.
Every one of those hits has a 50% chance to put Chorus Infection III on you for 2 seconds, unless you’re blocking at the time. Blocking stops the infection but disables your Shield for 2 seconds afterward, so you’re picking which problem you’d rather have. The full fight, animation by animation, is covered on the Chorusent page.
Exploration & Strategy
Gear for this one is about melee and about staying upright, since ranged weapons are off the table and both mobs here can shove you around. A 
Brush is the item people forget, and without it the Void Gem stays in the ground.
Order matters more than usual here, because the boss and all three spawners share the same floor. Only one of the three sits far enough out to mine with the Chorusent still out of range, so expect the boss to be up before the floor is clear.
Break the Spawners
Before anything wakes up
Each spawner only runs when a player is within 16 blocks, so you can reach one, mine it and back off before the other two notice. Clearing all three first means the boss fight doesn’t have a steady trickle of Choruslings feeding into it, which is the main thing that turns a manageable fight into a bad one.
Brush the Suspicious Sand
One block, one Void Gem
Find the single Suspicious Sand block on the ground floor and brush it before you start anything loud. Brushing takes a few seconds and being interrupted mid-way is annoying, and that block is the only Void Gem the tower will ever give you.
Empty the Shulker Boxes
Two on the floor, one up high
Open the two on the ground floor, then pillar or pearl your way up to the one set partway up the tower. Mine the boxes afterward as well, since you’ll get the Shulker Box itself on top of whatever it rolled.
Wake the Chorusent
Last, with the floor clear
Walk within 15 blocks to start it, then give up on any idea of ranged damage and commit to melee. Keep circling so the teleport strike lands behind you, and drink a 
Milk Bucket when Chorus Infection goes on, as it takes 3 off you at a time and keeps yanking you a couple of blocks out of position.
A bed won’t set your spawn in the End, so unless you have an 
Ender Anchor from the Space Station to charge, leave a stocked 
Ender Chest or a small platform bridged off to one side before you start. Dying in the middle of the floor with three spawners running is a long walk back, so spend the two minutes setting one up.
FAQ
They only generate in the End, on the surface of the islands in End Highlands and End Midlands, plus a few BetterEnd biomes if that mod is installed. They sit about 65 chunks apart, so they’re spread thin and you can travel a long way without seeing one. An Eye Of Chorus will find the nearest one within 100 chunks, which is far quicker than flying around looking.
Projectiles are canceled outright, and on top of that each one makes it teleport up to 7 blocks away. That covers Arrows, Tridents and anything else thrown, so a Bow only pushes the fight further around the ruin. The Choruslings ignore Arrows too, so melee is the only option in the whole building.
The recipe takes 2 Void Gems and a Withered Bone, and each tower holds a single block of Suspicious Sand with one gem in it. So you’ll need to clear two separate Ancient Tower Remains for one sword, with the Withered Bone coming off the Withered Abomination in the Soul Fortress Remains. Bring the Brush both times, as there’s no other way to get the gem out.
You can’t, at least not the first time, because the mask needs a Chorus Crystal and that only drops from the Chorusent you’re trying to kill. The first run relies on a Shield to block the infection and a Milk Bucket to clear it. After that first kill the mask strips Chorus Infection while it’s on your head, so a repeat visit is a lot calmer.
