— a Minecraft dimension mod for Fabric 1.21.1
A dimension beyond the stars is waiting.
Version 0.1.0-pre-alphaMinecraft 1.21.1
News · 30 October 2026
Pre-alpha 0.1.0 is available
The first playable build of The Astral Sea for Minecraft 1.21.1 (Fabric) is out as a pre-release on GitHub. Expect rough edges, and please back up your worlds.
- Version 0.1.0-pre-alpha
- Minecraft 1.21.1
- Fabric (Loader 0.19.5+)
In this version
- Nine biomes: Astral Highlands, Astral Wetlands, Shroom Viles, Astral Forest, Golden Forest, Frostveil Expanse, Caustic Slopes, The Fractured Heights and Shattered Furnace
- Over 80 creatures, plus corrupted forms through Universal Corruption
- Two dungeons with bosses: the Hollow Sanctum with the Astral Colossus, and the Toad Prince Dungeon
The mod
An entire dimension, written between the stars.
The Astral Sea is a Minecraft mod that opens a new dimension of floating highlands, glowing wetlands and fungal wilds. Every biome brings its own blocks, flora and creatures.
Gather Keldite and Astral Dust, master the Astral Furnace and the Astral Infuser, and forge equipment strong enough for what waits in the depths: the Astral Colossus in the Hollow Sanctum and the Toad Prince beneath the Wetlands.
Biomes · 01 / 10
Astral Highlands
Golden grass terraces above the Astral Sea. Bison herds, Starwhales and the way down into the Hollow Sanctum.
- Terraced plateaus
- Starwhales
- Hollow Sanctum
Creatures · Astral Highlands
Life, but not as you know it.
Herds of Astral Bison drift across the highlands. Others are less friendly, and you will meet them soon enough.
Meet the Astral BisonMechanics
Rules of another world.
Five things that work differently here. Hover or tap a tile for the rules.
Astral Water
It lifts players and animals towards the surface.
Astral Water
- Buoyancy for players and animals.
- Enchanted Astral Water bounces you back.
Spirit Storms
Find cover: under open sky your 20-second reserve drains.
Spirit Storms
- Out in the open, your 20-second Spirit Exposure reserve drains, and then you take 1.5 damage every 2 seconds.
- Caves, overhangs and covered rooms protect you, and the reserve refills there in 10 seconds.
Runecrafting
Carve runes into stone, forge them into gear.
Rune effects come later
Runecrafting
- The second slot needs a tier 2 Runeforge and the legendary slot tier 3.
- Sword runes only fit swords and armour runes only fit armour.
Universal Corruption
15 % larger, 25 % more health and damage.
Universal Corruption
- Corrupted creatures are 15 percent larger, with 25 percent more health and damage and 10 percent more speed.
- They stay that way and do not despawn.
Astral Adaptation
Vanilla tools mine astral stone at 8 % speed here.
Astral Adaptation
- Vanilla tools mine astral stone and ore at 8 percent speed inside the Astral Sea.
- Astral tools mine vanilla stone at half speed outside it.
Status effects, the soul system and more rules of the dimension.
All mechanics
Dungeons & Bosses
Something sleeps beneath the Sanctum.
The Hollow Sanctum teaches you how to survive what waits at its heart. We won't spoil the rest.
Enter the Archive