Better Ancient Cities and Deep Dark:

You need OptiFine, or the ETF or EMF mods, to see the new mob.

Reinforced Protector:

The Reinforced Protector is similar to a Blaze or Breeze.

It appears when you approach certain areas within Ancient Cities (once you've killed them all, they don't respawn).

It has 100 health.

It attacks in melee and leaps near players to deal area-of-effect damage.

Upon death, it doesn't drop anything, at least for now.

Sculk Jaw:

This block generates in the Deep Dark; if you stand on it, it will deal a small amount of damage and prevent you from moving unless you jump or break it.

Deepslate Chest:

Trap chests are replaced with Deepslate chests and now generate in Ancient Cities; they can be broken with a pickaxe and are crafted from Deepslate or Cobblestone Deepslate.

More Pottery Shards and Decorated pots:

Decorated pots and flowerpots made of Deepslate will generate in Ancient Cities.

New pottery shard designs, exclusive to Ancient Cities.

Placing a dead bush in a flowerpot will result in a Deepslate texture.

Decorated flowerpots made with pottery shards from the base game also feature a Deepslate texture. This is because, while it is possible to add custom pottery shards, the top texture of a decorated flowerpot cannot be changed.

New Advancements:

Translation:

This data pack includes translations for items, advancements, the protector name, and death messages in English, Spanish, Portuguese, French, and Chinese.

Credits

I created some elements for this datapack a couple of years ago for a server I played on with friends in version 1.20.1, but I’ve only just gotten around to updating them and uploading them. So, if any of the sources I’ve cited below aren’t entirely accurate, please let me know!

For the texture of the decorated pots, I drew inspiration from the idea of:

Decorated Pot, inspired by this idea

The model I used for the flower pot comes from the texture pack: Fresh Flower Pots

Flower Pots Model

I got the idea to create this mob thanks to the image in this post:

Reinforced Protector, inspired by this idea"

I modified the deepslate chest based on the following texture pack:

Deepslate chest, modified from this one