Be sure the minetest.conf file in the main Minetest directory doesn't have any parameters who are in conflict with the minetest.conf file from the hades_revisited directory. Especially mapgen parameters or stuff like give_initial_stuff = false
Hades Revisited only works in mapgen v6.
There only 1 biome, with the focus on terraforming.
Not everyone will like this game. But maybe there are some freaks out there ;-)
Take another map seed if you spawn on lava.
External mods can make some trouble, there are many changes in default

Background story

An attempt to colonize planet Hades went horribly wrong: Your colony ship crashed and you survived with very limited supplies. Hades is a very young planet and characterized by highly volcanic activities and a lot of fertile ash. Asteroids have brought some water on Hades. So there are the basics for life, you just need to help it to get the nature going, make the planet habitable and survive. Not every colonist has duly arrived. Most of them have been mutated and strayed around the planet. But for some unknown reason they don't suffer water. There are creatures and most of them live in the underground and darkness.

How to start:

You start with the following items: 1 steel pickaxe, 12 apples, 1 wall lamp and a stick. Watch out for flowing lava above you at first!

Next you should dig some stone to craft a stone sword with the stick. Now explore the area and search for some water.

Dig some stone and ash to craft fertile sand and place it in neighbor to water to become dirt. Take a dirt and a apple to craft a sapling. Plant the sapling on dirt to become wood and leaves from the tree. If you ran out of apples or lost your pickaxe, kill some mutants. They sometimes drop apples, pickaxes and other things. Make more dirt and place it near water.

Take 2 mossy stone (near water) and a dirt to craft grass.

Grass + dirt = jungle grass.

Dig the grass and the junglegrass to get some seeds.

Plant the seeds on the soil that you have placed over the water source.

And now survive with the crafting guide.

Things you should know

Block transformations

Fertile sand (which must be crafted) turns into dirt in the near of 10 nodes to water and direct contact of a dirt.
Volcanic ash turns into fertile sand if leaves are nearly.
Volcanic ash slowly turns into clay when next to water.
Flowing water turns lava source into water source and flowing lava into volcanic gravel.
Stone, tuff and cobblestone become burned when next to lava.
Stone, tuff and cobblestone become mossy when next to water.
Mossy cobblestone turns into gravel when next to flowing water.
Chondrite turns into marble if it is below -500 and it must be in near 4 nodes to lava and it also must have direct contact to water.
Volcanic gravel turns into obsidian below Y=-1000. It must have direct contact to lava and water must be nearly.
Sugarcane spawns near of papyrus. It dosnt need water to grow, just dirt

Other gameplay stuff

There is no fire
Beds do not allow you to skip the night, they only set the spawn point
Volcanic gravel can only be dug by a shovel.
Mobs spawn on stone, ash and tuff
Tuff is too breakable for tools so it can't be used to craft stone tools
There are no buckets, you need a water pump to spread water.
Weak torches can be upgraded with a string to bright torches
Plants grow with light level of 8 or higher. Underground farming is thus possible
2 emeralds = 1 sapphire. 2 sapphires = 1 ruby. 2 rubies = 1 diamond.
With the Staff of Gaia you can turn following blocks into dirt: ash, fertile sand, burned stone, stone, cobble, mossy stone, tuff, burned tuff, mossytuff, mossy cobble
Pale tree saplings can be plant on ash
Cacti grow on ash
Prismatic furnance is faster than the original furnance and has more slots

Ores

Ores generate at and below the following Y levels:

Coal: +60
Iron: 0
Copper: -115
Tin: -115
Mese: -200
Gold: -333
Emerald: +20
Sapphire: - 300
Ruby: -900
Diamond: -1200
Max. ore generation at -10000

Hints

A save mining experience:

w = water
l = ladder
o = light
s = stone
- = air
X = lava

***********
ssswlsss
ssswlsss
ssswloss
ssswlsss
ssswlsss
ssswssss
ss-w--ss
ss-w--ss
XXXXXXXX
ssssssss
***********

List of external mods (incomplete)

Important: A lot of the mods used in this game have been heavily changed from their original.

hades_furniture (based on 3dforniture) https://forum.minetest.net/viewtopic.php?id=2207

bags https://forum.minetest.net/viewtopic.php?id=3081

hades_bedrock (based on bedrock) http://www.moontest.org/viewtopic.php?f=11&t=9231

boost_cart https://forum.minetest.net/viewtopic.php?f=11&t=10172

hades_farming (based on farming_plus) https://forum.minetest.net/viewtopic.php?id=2787

glowcrystals https://forum.minetest.net/viewtopic.php?id=9047

hades_mapgen_lakes (based on highlandpools) https://forum.minetest.net/viewtopic.php?id=8400

hades_itemshow (based on item_frames) https://forum.minetest.net/viewtopic.php?id=5600

hades_chests (based on kerova) https://forum.minetest.net/viewtopic.php?id=8054

mesecons https://forum.minetest.net/viewtopic.php?t=628

mobs (Mobs Redo) https://forum.minetest.net/viewtopic.php?t=9917 https://forum.minetest.net/viewtopic.php?f=15&t=9184

pipeworks https://forum.minetest.net/viewtopic.php?t=2155

plantlife (old destroyed code) https://forum.minetest.net/viewtopic.php?id=3898

signs_lib https://forum.minetest.net/viewtopic.php?id=2041

hades_trash (bassed on trash_can) https://forum.minetest.net/viewtopic.php?id=6315

travelnet https://forum.minetest.net/viewtopic.php?id=4877

vines https://forum.minetest.net/viewtopic.php?id=2344

Licensing

This game is free software. It has been licensed under these licenses:

GNU LGPLv2.1 (or later) for the code
CC BY-SA 3.0 for the media

Some mods have separate licenses:

hades_furniture: GPLv2
travelnet: GPLv3
bags: New BSD License
hades_bedrock: zlib license
signs_lib: LGPLv3
mesecons (entire modpack): LGPLv3 for code, CC BY-SA 3.0 for media
hades_bushes: WTFPL for code, CC BY-SA 4.0 for media

For detailed credits and author information, check out the readme files of the individual mods (in the mods directory).

Sorry for the mess, it might be cleaned up later.