World
Legacies introduces a plethora of new biomes, structures and much more. Whilst not feasible to cover them all here, there's at least some documentation.
Biomes
Do note that whilst pretty much every vanilla biome has seen either major or minor additions (new blocks, mobs, etc - they will not all be covered here). This section specifically focuses on a few of the larger biome overhauls and new biomes, however will absolutely not include all new biome content added in Legacies, not by a long shot.
Forests
- Maple Forest
- Dying Forest
- Snowy Dying Forest
- Golden Forest
- Windswept Jungle
- Sparse Windswept Jungle
- Rainforest
- Pine Taiga
- Snowy Pine Taiga
- Old Growth Pine Taiga - Overhaul
- Savanna - Overhaul - Overhaul
Swamps
- Fen
- Cypress Wetlands
- Swamp - Overhaul
Fields
- Golden Fields
- Flower Fields
- Tundra
Deserts
- Oasis
Rivers & Beaches
- Cold River
- Cold Beach
- Lukewarm River
- Lukewarm Beach
- Tropical River
- Tropical Beach
- Warm River
- Arid Shore
- Golden River
- Snowy Shore
Caves
- Mesoglea Caves
- Magmatic Caves
- Frozen Caves
End
- Veiled Woodlands
- Magnia Fields
- Celestial Grove
- Corrupt Barrens
- Void Skies
- Void Sky Islands
- Void Depths
And More
- many more biome overhauls and additions to discover!
Structures
Do note that many structures have been made rarer in order to preserve the sense of isolation that older versions were known for whilst leaving room for the addition of a plentiful amount of new structures to increase exploration variety.
Surface
- Ruins
- Forest Ruins
- Obelisks
- Ruined Libraries
- Swamp Village
- Jungle Village
- Pale Cabin
- Swamp Hut - Overhaul
- new Illager structures
- new archaeology ruins
Caves
- Simple Dungeon
- Deep Dungeon
- Arid Dungeon
- Infernal Dungeon
- Frozen Dungeon
- Verdant Dungeon
- Deep Ruins
- Sculk Ruins
- Catacombs
- Remnants
- Underground Cabins
- Stronghold - Overhaul
Nether
- Scaffholding
- Citadel
- Ruined Aether Portal
- Spire
End
- End City - Overhaul
- Mirestone Ruins
- End Ruins
- End Remnants
Worldgen
Here are some of Legacies' many worldgen tweaks
Overworld
- terrain generation is now cut off at y320 rather than y256
- underground rivers now generate
Biome & Cave Depth
- ore variants have been added for Andesite, Diorite, Granite, Dolerite, Tuff, Sandstone & Red Sandstone
- Sandstone extends deeper below Deserts
- Red Sandstone extends deeper below Badlands
- Andesite replaces Stone in cold regions
- Diorite replaces Stone in tropical regions at high y-levels
- Granite replaces Stone in arid regions
- Dolerite replaces Stone in freezing regions
Nether
- the Nether is now 192 blocks tall
- Quartz and Gold ore veins now generate, much like the Overworld's Copper and Iron ore veins
- Nether biomes now generate in 4d, allowing for vertical placement differentiation
End
- completely overhauled terrain with Enderscape
- new Purpur & Ametrur clusters