Call of the Occult

This mod pack has a sort of diesel punk, exploration and horror aesthetic. You can do anything from creating factories and towns, to completing rituals to both summon or repulse various horrors.

There are several hardcore survival elements as well, from thirst, temperature, to seasons, pollution, nutrition, and food spoilage.

Technology Mods

Create (and many accompanying addons)

Immersive Engineering (and many accompanying add-ons)

Magic Mods

Occultism

Botania

Hexeri

Ars Noveau

Sons of Sin

Exploration Mods

Undergarden

The Twilight Forest

Aether

YUNG's Addons

Terralith

Deeper and Darker

Dimentional Doors

Dungeon Crawl

Bygone Nether

Tropicraft

Geophillic

Town Building Mods

Mine Colonies

And Accompanying Addons

Difficulty Mods

Whisper Woods

Born in Chaos

Zombie Awareness

Pollution of the Realms

Eyes in the Darkness

Majurz's Progressive Difficulty

Progressive Bosses

Mowzie's Mobs

Ice and Fire Dragons

Raided

Illagers Wear Armor

It Takes a Pillage

Nyf's Spiders

Enhanced Hordes

Creeper Overhaul

Enderman Overhaul

Nutrition

Serene Seasons

Spoiled

Cold Sweat

Thirst was Taken

Cave Spelunking

True Darkness

Rough Tweaks

Misc Mods

Artifacts

Quark

Farmer's Delight series

Let's Do Series

Candlelight Series

Unified & All the Ores

Eureka & Valkyrien Skies

Backpacked

Sleeping Bags

Journeymap

Supplementaries

Alex's Mobs

Naturalist

Beekeeping