🌊🐚 Aino’s Underwater Adventures (Mermaid & Siren) 1.20.1

UPDATE: I updated the entire mod list and replaced the old mermaid tail resource pack with my own. I removed and added mods based on performance, compatibility with updates, and usefulness. Check the mod list at the bottom of the description to see what was added and removed. If you encounter any issues, please leave a comment and I will try to fix them. I will not update this modpack above 1.20.1 currently as most mods rely on 1.20.1, however I did update the modloader.

Hi! I’m Aino. I originally created this modpack for personal use, but decided to upload it in case others would enjoy it as well. This modpack is centered around playing as a Mermaid or Siren and exploring the ocean and underwater world.

Getting Started
You will need to choose either the Merling or Siren origin. Both give you a default tail, but they have some differences.

Merling Origin
In water, Merlings can breathe and interact normally, see clearly, and swim faster. However, Merlings cannot stay outside of water for long because they will suffocate — they cannot breathe on land.

Siren Origin

In water, Sirens can breathe and interact normally, see clearly, and swim faster. Sirens regenerate health very quickly underwater and have two special abilities:

Siren’s Song – Turns hostile mobs around you friendly for a short time.

Captivating – You gain favors from villagers, resulting in cheaper or better trades.

However, Sirens do not belong outside of water, which means they cannot regenerate health on land. They also do not belong near fire, as it will result in instant death.

(Check your keybinds for the Siren Song and Captivating abilities.)

Tail Customization
To recolor your tail, you will need to craft the Sea Necklace, which is one of the items included in the MerMod. The Sea Necklace can be colored with different dyes and the Tail Gradient item depending on which color or color mix you want.

There is also a Mermaid Bra that you can recolor and add to the Sea Necklace. Other items you can add to the Sea Necklace include:

Tail Moisturizers (lets you keep your tail outside of water)
Glowing Pearl (gives your tail a glow effect)

For more information, visit the MerMod official mod page linked in the bottom of the description.

IMPORTANT: Unless you want to keep the default MerMod tail, remember to enable the Aino’s Tails resource pack and place it above all other resource packs for it to work correctly.

Data Packs

There are two data packs that need to be manually enabled:
Craftable Prismarine Shards
Craftable Prismarine Crystals

How to Enable Data Packs

Create a new world.
Click Data Packs in the world creation menu.
Open Open Pack Folder.
Copy the data packs from the modpack datapacks folder into this folder.
Go back to Minecraft and click Done.
Move the data packs from the left side to the right side (Enabled).
Create the world.

What Can You Do as a Mermaid or Siren?

You can venture through the seas, build an underwater home or beach house, find and store treasures, discover many sea creatures, collect seashells and pearl oysters, cook guardian soup, customize and admire your tail, tame animals and keep pets, learn and practice magic, lure sailors, explore abandoned ocean structures, fight dangerous sea creatures, or even explore land for animals, structures, and resources.

Do anything your heart desires. However, be careful — the ocean can be dangerous, especially in deeper and darker areas.

The Modpack Includes
Animals and pets, pirates and ships, decoration and furniture, fairy lights, many aquatic creatures, magic and witchcraft, many biomes, various foods including seafood, structures on land and in water, multiple shaders, and multiple resource packs that you can enable.

Disclaimer: I do NOT own the mods, data packs, or resource packs in this modpack. I only own the Aino's Mermod Mermaid Tail Retexture 🤍 (Resource Pack Addon) resource pack.

All mod, data pack and resource pack links are listed below — please visit the original mod pages for more information.

As of 25.3.2026.

Hi! I’m Aino. I originally created this modpack for personal use, but decided to upload it in case others would enjoy it as well. This modpack is centered around playing as a Mermaid or Siren and exploring the ocean and underwater world.

Getting StartedYou will need to choose either the Merling or Siren origin. Both give you a default tail, but they have some differences.

Siren Origin

Captivating – You gain favors from villagers, resulting in cheaper or better trades.However, Sirens do not belong outside of water, which means they cannot regenerate health on land. They also do not belong near fire, as it will result in instant death.

Tail CustomizationTo recolor your tail, you will need to craft the Sea Necklace, which is one of the items included in the MerMod. The Sea Necklace can be colored with different dyes and the Tail Gradient item depending on which color or color mix you want.

Aino's Underwater Adventures (Mermaid & Siren)