Ancient Cities are the big structures from vanilla Minecraft that sit down in the Deep Dark, and the Deeper and Darker mod uses them as the starting point for the rest of its content. Each one has the frame you’ll need for the Otherside Portal, as well as the Warden, which now drops the item needed to light it.
The mod also adds some new loot to the chests, and it fills the walls with Ancient Vases that might have something living inside them. You’ll probably come back more than once, first to light the portal and then again later on, when you’re after the Smithing Templates used for Warden gear and Resonarium gear.
Finding One
You’ll only find these cities in the Deep Dark, which is a biome that’s deep underground below Y 0, and it’s usually under mountains. They’re very big, and you’ll know when you’ve found one, as the floor will turn into Deepslate Bricks and 
Sculk, with 
Sculk Sensors and 
Sculk Shriekers all over the paths.
It’s worth sneaking the whole time you’re inside one, as walking, jumping and even opening chests will make vibrations that the sensors pick up. Wool and Carpet don’t make a sound when they’re walked on, which is why a path of Wool through the busier parts of a city can be a big help.
The Portal Frame
The tall archway of 
Reinforced Deepslate in the middle of the city is actually the frame for the Otherside Portal, and once Deeper and Darker is installed you’re able to light it. The opening is 20 blocks wide and 6 blocks tall, and to light it you’ll need a 
Heart of the Deep, which only the Warden drops.
Sculk will often spread over the frame and into the opening, and if anything is left inside, the portal won’t light. So it’s worth clearing away the 
Sculk Veins before you try using the heart, and there’s a full walkthrough of the steps on the portal’s own page.
The Warden
The Warden is summoned once the city’s Sculk Shriekers have been set off four times, and it’ll climb up out of the ground close to whoever set them off. It has 500 health, which equates to 250 hearts, and its Sonic Boom goes straight through armor and 
Shields, so it’s not a fight to take on lightly.
Warden Drops
Every one of them will drop a Heart of the Deep and a few 
Warden Carapace, as well as the 
Sculk Catalyst it drops without the mod. The heart is used to light the portal or craft the 
Sonorous Staff, while the Carapace goes into the 
Reinforced Echo Shard and the 
Ancient Compass.
One heart is enough to light the portal, so you won’t need to fight another Warden until you want a Sonorous Staff or a second portal. Each new Warden is just as tough as the last, which makes it worth leaving the city once you’ve got what you came for, before the shriekers can call up another.
New Chest Loot
Deeper and Darker adds three items to the chests around an Ancient City, and each chest rolls for them on its own. That makes looting every chest in the city the easiest way to get both Smithing Templates, as you’ll usually come away with a few of each.
| Item | Chance per Chest | Used For |
|---|---|---|
 Warden Upgrade Smithing Template | 45% | Upgrading Netherite gear to Warden gear |
 Resonarium Upgrade Smithing Template | 45% | Upgrading Diamond gear to Resonarium gear |
| Warden Carapace | 20% | Reinforced Echo Shards and the Ancient Compass |
Both templates can be copied at a 
Crafting Table, so you’ll only need one of each to get started. The Resonarium one also turns up in Stronghold corridor chests and Trial Chamber rewards, though it was added in 1.4, so it isn’t in the 1.20.1 version of the mod, which stops at 1.3.3.
Ancient Vases
The walls of every Ancient City are lined with 
Ancient Vases, and these will break open to give you a bit of loot, like some Iron, a few Gold Ingots or even a Diamond. Some of them are fakes, though, and if you break one of those it will release a Stalker or a few Sculk Leeches instead.
Fake Vases
There’s a 16% chance of any vase being a fake, and most of the time it’ll be Sculk Leeches rather than a Stalker that comes out. Mining one with Silk Touch picks it up without breaking it, and the vases you place yourself are always safe, which is covered more on the Ancient Vase page.
Getting Loot Safely
Fake vases can’t happen on Peaceful, or with mob spawning turned off, so those vases will only ever drop loot. On any other difficulty, it’s a good idea to clear out the area before breaking a row of them, as a Stalker showing up in the middle of a city can quickly wake the Warden as well.
FAQ
The Warden is the same as it is in vanilla Minecraft, with the same 500 health and the same Sonic Boom attack. The only thing that changes is what it drops, as it will now drop a Heart of the Deep and 1 to 3 Warden Carapace as well as its Sculk Catalyst.
The portal is the big archway made of Reinforced Deepslate in the center of the city, and it’s often covered in Sculk. Without a mod it’s just there for decoration, but with Deeper and Darker you’re able to light it with a Heart of the Deep, which takes you to the Otherside.
Each chest in an Ancient City has a 45% chance of holding one, so looting a whole city will usually turn up a few. You can copy it with 7 Diamonds and a block of Sculk as well, and Ancient Temples in the Otherside have a small chance of one in their secret chest.
Warden Carapace shows up in 20% of Ancient City chests, and Ancient Vases have a small chance to drop one too. The Warden is still the most reliable source, as it drops 1 to 3 every time, and some chests in the Otherside’s Ancient Temples have them as well.
