Loria (alpha)
siegment

Survival in hardcore acid-alien sci-fi themed world

XaEnvironment
AiTechEye

A game that aims to contain lots of environments and things.

Nether
PilzAdam

Adds a deep underground realm with different mapgen that you can reach with obsidian portals.

Hades Revisited
Wuzzy

You have stranded on the planet Hades. Use your limited supplies to survive and use terraforming to create a beautiful habitable place. (EARLY TEST VERSION)

Underground Challenge
Hume2

Explore all 62 underground biomes!

NodeCore Lignite
Winter94

Adds Lignite, an ore of coal.

Grave
ElCeejo

Adds a eerie dimension called "The Grave".

Trucraft
PolySaken

An alternative crafting system done entirely in the world.