This is the Valhelsia 3 - 1.16 modpack but with a few additional mods added such as Pollution of the Realms and Steve's Universe.

Requirements:

Minimum allocated RAM: 4 GB
Recommended allocated RAM: 5-6 GB normally, or 6-8GB for those with OptiFine, high render distance, increased video settings, HD resource packs, and/or shader packs.

There is a guide to allocating RAM here, on our wiki.
OptiFine: You can find the necessary information about OptiFine compatibility and setup in our Knowledgebase.

Mods:

LAST UPDATE: 3.2.4

Abnormals Core API (by TeamAbnormals)
Abnormals Delight (by TeamAbnormals)
Absent by Design (by Lothrazar)
Abundance (by ex0planetary)
AI Improvements (by DarkGuardsman)
AIOT Botania (by MelanX)
Akashic Tome (by Vazkii)
Alex's Mobs (by alex1the1666)
Allurement (by TeamAbnormals)
AmbientSounds 3 (by CreativeMD)
Apotheosis (by Shadows_of_Fire)
AppleSkin (by squeek502)
Aquaculture 2 (by Shadowclaimer)
Archer's Paradox (by TeamCoFH)
Armor Toughness Bar (by tfarecnim)
Artifacts (by ochotonida)
Astral Sorcery (by HellFirePvP)
Atmospheric (by TeamAbnormals)
AutoRegLib (by Vazkii)
Autumnity (by TeamAbnormals)
Back Tools (by ohaiiChun)
Bayou Blues (by ex0planetary)
Bamboo Blocks (by bageldotjpg)
Bed Benefits (by DarkhaxDev)
Bedspreads (by TheIllusiveC4)
Berry Good (by TeamAbnormals)
Better Advancements (by way2muchnoise)
Better Badlands (by Gkoliver)
Better Biome Blend (by FionaTheMortal)
Better Burning (by DarkhaxDev)
Better Title Screen (by Girafi)
Biomes O' Plenty (by Forstride)
BlockCarpentry (by PianoManu)
Blood Magic (by WayofTime)
Bones (by ochotonida)
Bookshelf (by DarkhaxDev)
Botania (by Vazkii)
Buzzier Bees (by bageldotjpg)
Caelus API (TheIllusiveC4)
Carry On (by Tschipp)
Cat Jammies (by Buuz135)
CC: Tweaked (by SquidDev)
Cherished Worlds (by TheIllusiveC4)
Chisels & Bits (by AlgorithmX2)
Client Tweaks (by BlayTheNinth)
Cloth Config API (by shedaniel)
Clumps (by Jaredlll08)
Comforts (by TheIllusiveC4)
ConnectedTexturesMod (by tterrag1098)
Controlling (by Jaredlll08)
Cooking for Blockheads (by BlayTheNinth)
Cosmetic Armor Reworked (by LainMI)
Crafting Tweaks (by BlayTheNinth)
Create (by simibubi)
Curio of Undying (by TheIllusiveC4)
Curios API (by TheIllusiveC4)
Curios Quark Oddities Backpack (by 6LeoMC)
Curious Armor Stands (by ochotonida)
Curious Elytra (by TheIllusiveC4)
Curious Shulker Boxes (by TheIllusiveC4)
Customizable Elytra (by Hidoni)
Dark Utilities (by DarkhaxDev)
Dash (by ModdingLegacy)
~~DataFixerSlayer (by Vazkii)~~
Decorative Blocks (by stohun)
Decorative Blocks modded compat (by Evo_934)
Default Options (by BlayTheNinth)
Druidcraft (by VulpTheHorseDog)
Dynamic Surroundings (by OreCruncher)
Eidolon (by elucent_)
Enchanted Book Redesign (by tfarecnim)
Ender Storage 1.8.+ (by covers1624)
Engineer's Decor (by wilechaote)
Ensorcellation (by TeamCoFH)
Environmental (by TeamAbnormals)
Enhanced Mushrooms (by Ep1c312)
Extended Lights (by Polyvalord)
Extra Boats (by TeamAbnormals)
Fairy Lights (by pau101)
Farmer's Delight (by vectorwing)
Fast Leaf Decay (by olafskiii)
FastFurnace (by Shadows_of_Fire)
FastWorkbench Minus Replacement (by tfarecnim)
FerriteCore (by malte0811)
Fishing Real (by PricelessKoala)
Flux Networks (by sonar_sonic)
Forbidden and Arcanus (by cesar_zorak)
FTB Backups (by FTB)
FTB GUI Library (by FTB)
Game Stages (by DarkhaxDev)
Goblin Traders (by MrCrayfish)
Health Overlay (by Terrails)
iChunUtil API (by ohaiiChun)
Immersive Engineering (by BluSunrize)
Immersive Petroleum (by Flaxbeard)
Immersive Posts (by TwistedGate)
In Control! (by McJty)
Incubation (by Markus1002)
Industrial Foregoing (by Buuz135)
Inventory HUD+ (by dmitrylovin)
Inventory Sorter (by cpw)
Iron Chests (by ProgWML6)
Jade (by Snownee_)
JAOPCA (by TheLMiffy1111)
JEI Enchantment Info (by Phylogeny)
JEI Integration (by SnowShock35)
Just Enough Items (by mezz)
Just Enough Resources (by way2muchnoise)
KleeSlabs (by BlayTheNinth)
KubeJS (by LatvianModder)
KubeJS Blood Magic (by LatvianModder)
KubeJS Create (by LatvianModder)
KubeJS Immersive Engineering (by LatvianModder)
KubeJS Mekanism (by LatvianModder)
KubeJS UI (by LatvianModder)
LazyDFU (by tuxed, ported by Corgi_Taco)
Leap (by ModdingLegacy)
Light Overlay (by shedaniel)
Macaw's Bridges (by sketch_macaw)
Macaw's Doors (by sketch_macaw)
Macaw's Furniture (by sketch_macaw)
Macaw's Roofs (by sketch_macaw)
Macaw's Trapdoors (by sketch_macaw)
Macaw's Windows (by sketch_macaw)
Mekanism (by bradyaidanc)
Mekanism Additions (by bradyaidanc)
Mekanism Generators (by bradyaidanc)
Mekanism Tools (by bradyaidanc)
MineColonies (by H3lay)
MineColonies for ComputerCraft (by uecasm)
Miner's Helmet (by ModdingLegacy)
Mouse Tweaks (by YaLTeR)
Mowzie's Mobs (by bobmowzie)
Music Maker Mod (by xerca0)
Mystical World (by EpicSquid315)
MythicBotany (by noeppinoeppi)
Nature's Compass (by Chaosyr)
Neapolitan (by TeamAbnormals)
Neat (by Vazkii)
Neon Craft Mod (by Polyvalord)
Netherite Horse Armor Mod (by louie_cai)
Notes (by Chaosyr)
OldJavaWarning (by DarkhaxDev)
Open Loader (by DarkhaxDev)
OpenBlocks Elevator (by vsngarcia)
Overloaded Armor Bar (by tfarecnim)
PackMenu (by Shadows_of_Fire)
Paintings ++ (by AbsolemJackdaw)
Pane In The Glass (by MongoTheElder)
Patchouli (by Vazkii)
Peculiars (by cosmicgelatin1)
Performant (by someaddon)
Personality (by TeamAbnormals)
Placebo API (by Shadows_of_Fire)
Polymorph (by TheIllusiveC4)
Powah! (by owmii)
Psi (by Vazkii)
Quark (by Vazkii)
Quark Oddities (by Vazkii)
RandomPatches (by TheRandomLabs)
ReAuth (by TechnicianLP)
RecipeBuffers (by malte0811)
Refined Storage (by raoulvdberge)
Refined Storage Addons (by raoulvdberge)
Refined Storage for ComputerCraft (by uecasm)
Refined Storage: Requestify (by Buuz135)
Runelic (by DarkhaxDev)
Savage & Ravage (by TeamAbnormals)
Save My Stronghold! (by YUNGNICKYOUNG)
Scuba Gear (by ModdingLegacy)
Server Tab Info (by black_dog20)
ServerConfig Updater (by Darkere)
Simple Discord Rich Presence (by Sunekaer)
Snow Under Trees (by bl4ckscor3)
Sound Device Options (by ichttt)
Spark (by Iucko)
Step (by ModdingLegacy)
Storage Drawers (by Texelsaur)
Structure Gel API (by ModdingLegacy)
Structurize (by H3lay)
Supplementaries (by MehVahdJukaar)
SwingThroughGrass (by exidex)
Tetra (by mickelus)
Tetranomicon (by syrikalis)
The Conjurer (by ModdingLegacy)
The Mighty Architect (by simibubi)
The Endergetic Expansion (by TeamAbnormals)
Titanium (by hrznstudio)
Toast Control (by Shadows_of_Fire)
Tool Stats (by DarkhaxDev)
Torch Slabs Mod (by EndlesNights)
Torchmaster (by xalcon)
Transport (by Sky_Som)
TrashSlot (by BlayTheNinth)
Upgrade Aquatic (by TeamAbnormals)
Valhelsia Structures (by ValhelsiaTeam)
Valhelsia Tweaks (by ValhelsiaTeam)
Waddles (by Girafi)
Waila Harvestability (by squeek502)
Waystones (by BlayTheNinth)
Windowlogging (by mc_Grimmauld)
Xaero's Minimap (by xaero96)
Xaero's World Map (by xaero96)
YUNG's Better Caves (by YUNGNICKYOUNG)
YUNG's Better Mineshafts (by YUNGNICKYOUNG)

Voidflower

Abnormals Delight

Absent by Design

Abundance

Advanced Chimneys

Advanced Peripherals

AI Improvements

AIOT Botania

Akashic Tome

Alex's Mobs

Allurement

AmbientSounds 6

Apotheosis

AppleSkin

Aquaculture 2

Archer's Paradox

Architectury API

Armor Toughness Bar

Artifacts

Astral Sorcery

Atmospheric