Do not cry.

                  Once upon a midnight dreary, while I pondered, weak and weary

Over many a quaint and curious volume of forgotten lore—

    While I nodded, nearly napping, suddenly there came a tapping,

As of some one gently rapping, rapping at my chamber door.

“’Tis some visitor,” I muttered, “tapping at my chamber door—

            Only this and nothing more.”        -The Raven by Edgar Allan Poe

Inside:

Abyssalcraft and Lycanites are the main mods, but to become stronger there are EvilCraft, Vampirism, Mahou Tsukai. And many more little mods to change the way you know Minecraft.
The progression of the mod is explained in-game through a book.

Specs:

-Needs Minecraft 1.12.2, Forge 14.23.5.2847 or above.

-It is strongly suggested to use Optifine 'OptiFine 1.12.2 HD G F5'.

-I recomend to use the resourcepacks inside the modpack.

 I didn't think about a server side version, so if you want to play with your friends,  you need to arrange on your own.

Known BUG & ISSUES:

-Very very rarely you might lose everything after dying.

-When teleporting you might get stuck nowhere, caused with full RAM allocation memory.

-Rarely you might be able to sleep.

-Blood vision (from Vampirism) breaks the visual, do not absolutely use it. Due a bug with shaders.

External mentions:

That I added in the modpack but couldn't quote.

-Chocapic13 shader: https://www.curseforge.com/minecraft/customization/chocapic13-shaders

-Lycanites mod resourcepack: https://www.curseforge.com/minecraft/texture-packs/lycanites-mobs-32x

-Tissou'sZombie resourcepack: https://www.curseforge.com/minecraft/texture-packs/tissous-zombie-pack-optifine-1-7x-1-15

-HSBC shader by crushed pixel: https://www.youtube.com/watch?v=zgGl-xLlOcs

AND EVERY MODDER THAT CODED EVERYTHING AND SHARED THE MODS, THANK YOU FOR YOUR SWEAT AND PAIN also joy.

Recommend to use internal shader or any other shader, but Chocapic13 is very very cool:

Settings for the Shader Chocapic13:

Use the latest available graphic driver. 

Requires at least 500 pixels on each axis on the target resolution to work properly. 

Leave Shadow quality to 1.00x in optifine menu, and use the shader options to change shadow resolution. 

Set sky to On in optifine settings.

Set "Old lighting" to Off or Default.

Ressourcepack with custom sky might not work.