WARNING: This mod contains spoilers for Stranger Things. Please support the official show on Netflix!

Welcome to Prim's Stranger Things Mod!

The Upside Down

"It's like home... But it's so dark and empty, and it's cold!" -Will Byers

A dark reflection of our world, the Upside Down is always there, you just can't see it. It's dark, covered in tendrils, filled with spores and choked with an omnipresent fog. It looks just like the home you're familiar with, but no human traces can be found. Except... traces of redstone from the other side may bleed through, allowing contact with home...

Getting to the Upside Down.

Reaching the Upside Down requires a gate between dimensions. These can be hard to find normally, however. A gate would require so much energy, it may disrupt the magnetic field! Grab yourself a compass and it will point toward the nearest gate. Follow it! It should be hard to miss.

Once you find a gate, you will have to push through the gross membrane to get in!

Welcome to other side...

 

 

The Upside Down is a rather eerie place. No one is here, no mobs, no animals, no people (besides you). You are free to explore as you please. Though everything you know from back home is here. Including chest items. There are strange vines over everything that wrap around blocks and seem to grow when you aren't looking... But, the Demogoron is always on the prowl. It will be searching for you and will attack at a random time between 2-5 Minutes.

The Redstone System

If you've seen Stranger Things, you may recall Will Byers (and later Nancy Wheeler, Eddie Munson, Robin Buckley and Steve Harrington) communicating with our world through the lights. This feature is present here! Your presence in the Upside Down will interfere with redstone back home. Causing it to activate when you're near.

 

The World Mirroring System:

The Upside Down is a mirror of the overworld, as such. It will copy all of your builds and the like over. When you first enter the gate (or use /initializeUpsideDown true), the game will load all player visited chunks into the Upside Down. Even removing water, lights and leaves! Keep in mind, the Upside Down is programmed to generate as a perfect copy of your world's seed, so if you leave the area you built in, you should still see new chunks being generated that fit the world. (Unless you use Season 5 generation, which is a gamerule.)

Consider:

The Upside Down only initializes once, when you first enter. So any new builds you make in the Overworld or Upside Down will not reflect. Unless you type the command: /initializeUpsideDown true. This command will re-initialize the Upside Down. Though this will erase all old chunks in the Upside Down. Removing anything in there that isn't in the Overworld.

The Monster:

"A monster... from America." -Dimitri Antonov

The Adult Demogorgon is the primary predator of the Upside Down. It is ferocious and strong, able to kill an ill-equipped human in seconds. It smells blood, if you happen to cut yourself, you may be in for a nasty surprise when it gets dark. If you aren't careful, you could end up it's next meal. Though, it doesn't like fire. So bring a match if you plan to fight this monster... Be careful, the Demogorgon is part of a hive mind. If you step on a vine for too long, it may alert the creature to your location. Shearing off a vine or using fire to chase them away is a good countermeasure. But if the monster sees you, it will pursue you relentlessly unless you distract it. Setting any Upside Down monster on fire will distract it and cause it to lose sight of you.

The Mind Flayer:

As of update 2.0, the mod has an overarching antagonist. The all power "brain" of the Upside Down. "Arthrodomius", "The Brain", "Him", "The Mind Flayer". Whatever you call it, the Mind Flayer is a godlike entity that rules the Upside Down. Everything that lives there not only serves the Mind Flayer, but is directly linked to it by being "Flayed". 

The Mind Flayer is not a mob, it is the Upside Down. Everything you do can effect how it thinks of you. Depending on your actions, it may see you as a THREAT, a VICTIM or as USEFUL. Each stat can co-exist. And changes based on certain things.

THREAT: Any aggression toward the Hive Mind will be met with extreme force. Attacking the creatures of the Upside Down, burning the Upside Down and killing the creatures with fire can anger the Mind Flayer. Once you reach a certain level, the Mind Flayer will be hunting you and randomly ambush you with hordes of Demodogs. Over time, this will increase to include full grown Demogorgons. There is not a lot of warning for this. You must be on your toes. You can also tell if the Mind Flayer is irritated if a red lightning storm begins in the Upside Down. The frequency of the lightning is determined by your level of THREAT.

VICTIM: Should you be taking too much abuse from the Hive Mind, The Mind Flayer will begin to see you as prey, not a predator. When this happens, you will start to hallucinate the Upside Down. These hallucinations will begin to get worse and worse. Eventually you will see the Mind Flayer watching you as it chases you down with a mass of particles. If these catch you for long enough, you are "Flayed" and part of the Mind Flayer's hive mind. But, if you can find a music disc and a joke box. You can escape this nightmare and lower your own VICTIM level. The Mind Flayer will try again, but that which is endured is conquered. You can do this. 

USEFUL: Gained only while flayed. This determines how often the Mind Flayer will try to take over your body. It grows the longer you are flayed. Once it's high, you are a liability to all your friends. But they can still help you.

All of these stats stay after death. But they do go down over time. Dying to a creature from the Upside Down can also lower your threat level a bit.

One more important part of this is AWARENESS. The Mind Flayer is not totally all-knowing. It has to know where you are to mount an attack. It can do this in two ways. Either a creature under it's control sees you, or you step on a vine for too long. Creatures under it's control mean any creature that is FLAYED. Including your friends. If the Mind Flayer loses sight of you, it will ESTIMATE your position based on the last place it saw you. 

So, Flayed? Whazzat? All Upside Down creatures are flayed by default. But mobs in your overworld may also become flayed. You can sometimes see this when black particles enter them. A Flayed mob will likely act very suspicious. Following you, running around when another flayed is burned and trying to avoid you. Though, take heed when attacking a Flayed mob. They may call in a horde of fellow Flayed to kill you. The Mind Flayer prioritizes flaying mobs you don't suspect. It will try harder to flay mobs at higher threat levels. 

You can save the Flayed, either yourself, your friends or mobs. Trap a flayed creature in a sealed up small room with fire or lava in it. As long as there is no solid blocks in the way, they will begin to panic and run around. This means it's working. Keep in mind for players that the Mind Flayer will take over their body and make them try to break out. They will use tools to try to break the walls, place blocks to smother lava, punch our fires, maybe even attack you. To prevent this, just make sure they don't have those resources. After about a minute of this, the Mind Flayer will leave. Resetting their victim and useful levels to 0. You can also unflay anything with the creative only item the "Hyperbolic Pulse Generator." But you can't unflay yourself with it.

The Infection:

The Mind Flayer is constantly trying to invade your world. Right below the Mothergate, you will find a larger second breach inside a massive cavern. You can't enter the second gate, but it has spread a large creature into your world. If your threat level rises, this creature will grow 9 sprawling tunnels called the Underdark below your feet. These tunnels can be identitifed by rotting grass above them. Sometimes, the tunnels will form a burrow point. At high enough THREAT level, they will burrow right up into your world and corrupt the surface into the Upperdark. The Upperdark is quite dangerous and nasty. It has a higher chance to appear in a village too. It's crawling with Demodogs, too. These can be stopped by burning tne Burrow Point below. This is only temporary and does infuriate the Mind Flayer.. But the area above will try to heal. The Tunnels pose a risk, as Demodogs will sometimes burrow out of them on the hunt. 

How do you defeat the Mind Flayer?

You can't kill it, let's be clear about that. But you can lock it off. As you explore the Upside Down, you may come upon a structure. If you go underground, you will find the X Meteorite. A strange relic from a world beyond even the Upside Down. If you use it, you gain a bit of the Mind Flayer's power. The power of Telekinesis.

Pressing P (rebindable) will toggle your powers. They're explained in game. But they give you a fighting chance against the Hive Mind. Left click to send out a psychic force, hold shift and right click to charge a wave of destruction. Hold right click to grab a targeted mob or shift right click for a block and mousewheel lets you push or pull what you're holding. You can use your scroll wheel to select a target in range if you aren't looking right at them. Hold shift and space to use a super jump which allows for a double jump. Tap shift only to put up a shield which blocks damage. Timing it right will parry the attack and knock the attacker back. If you're being attacked with a weapon, tapping right click after the attack is blocked with your shield will allow you to take the weapon with your powers and throw it whereever you want. If you're being grabbed by a foe with powers, mash P to escape. If you and a player are trying to grab the same mob, you must win a psychic struggle. You do this by mashing W or S. S will allow you to grab the creature from them. W will throw it back at them if you win. They can do the same, though. 

Use of your powers drains hunger, so keep yourself fed! 

Once you have these powers, you can take the fight to the Mothergate. Holding right click on the large underground mothergate will trigger a minigame. If you win this game, the gate closes, all nearby Upside Down creatures and Flayed in the Overworld die and the area becomes safe from incursion. All the tunnels die, too. This is permanent. This area is forever safe. But if you fail this minigame, you can get flayed by the Mind Flayer. While flayed, you can't close the gate.

Beware, while your area is safe. There are many more Mothergates open in the world. So those areas may not be safe. The Mind Flayer can still torment you and try to flay you while the gate is closed. But it can't send monsters. 

Upside Down Sickness:

The air in the Upside Down is very bad for you. The longer you are there, the worse it gets. You'll start feeling sick, then you'll begin to lose maximum hearts. The time this takes is much faster in the Underdark or Upperdark. Past a certain point, Demogorgon attacks may cause you to become infested. Should this happen, you will eventually cough up a slug. These are the infant form of Demogorgons. They're harmless, though. 

Demogorgon Domestication??

Yup. You can have a pet Demo! This is a bit of a long process. If you begin to feed a slug raw meat, it may start to like you. Over time, it will molt into a Pollywog. Pollywogs will die if exposed to light. So keep them in the dark and feed them when you can. They don't like to be overfed though. After a Pollywog, they become a Frogogorgon. Same deal as before, no heat, feed them. After this, they will become a Catogorgon. They will try to eat rabbits or cats. They become flayed and will run away. Don't despair! Your friend hasn't totally forgotten you. Sometimes, it may appear as a Demodog. Indicated by the glowing effect and the fact that it won't attack you. Unflay it, and it's your new best friend. All pets in this mod (including vanilla ones) will have a new set of mechanics. Hold right click over your pet and you can use a new UI to command them. They can have a home base, be sent home, attack on your command and follow between dimensions. As said, this replaces the only "sit or follow" mechanic for other pets too. Though not all pets have the same commands. Your Demodog will eventually hide itself in a cocoon and become a Demogorgon. Breaking this cocoon will kill it instantly. But once it hatches, your new friend is a fully grown Demogorgon who will fight for you! Unflayed/Pet Demos can't use their gates, but they aren't as weak to fire. They're free, and they are ever grateful to you.

Be careful though, trust building is fickle. If you harm your pet before saving it from the Mind Flayer. It will view you as a traitor and never want to be your friend again. 

The Flumph?

A brand new passive creature native to the Underdark. These little girlies are friendly, but they do still act as spies. Hurting them will really piss off the Mind Flayer, so try to avoid that. They're quite lazy, so they will sleep when left alone. So you can sneak by them. But, if they do hear/see you. They will approach and offer a friendly greeting. Oh, what a joy! They can be unflayed too and tamed with Living Tendrils. It's a fair bit easier for them. I think they like you more, anyway.

The Abyss:

As a fun bit of fanservice, you can visit the Abyss! Create a world with the S5 Generation gamerule set to true. The Upside Down will have a roof. If you have a compass, you can find a gate up there which will take you to the Abyss. There will be a weird little corpse monolith that indicates where the Mothergate relative to you. The Abyss is empty aside from some fun world gen I spent like 4 days on. There's not much to do here aside from get absotluley destroyed by the hordes of Demos. 

Future Plans:

This mod will be released in five major content updates, one for each season of the show. Each update will try to rework that season's ideas into a cohesive survival horror experience. While I want this mod to follow it's own artistic vision for features, asthetic and overall gameplay. I am not above changing my plans or adding fanservice for people who want it. No shame in a little fun, right? Each update is indicated by the first digit of it's update number, it works like this:

(Number of major update).(Number of small update).(Number of patch)

So a small patch for update 3.0 would be 3.0.1. But if I added something significant that will become update 3.1.0.

The updates:

Update Zero: (Released)

-Adds the Upside Down dimension.

-Adds a mothergate structure that allows access to the Upside Down.

-Adds a comprehensive system for importing and processing overworld chunks to the Upside Down allowing for build mirroring.

-Changes compasses to point at the mothergate.

-Adds some random trees with gates in them to access the Upside Down.

Update One: Close Encounters with the Other Side (Released): 

-Adds the Demogorgon that can kidnap you to the Upside Down and hunts you mercilessly.

-Adds the bleeding effect that alerts the Demogorgon.

-Adds the Upside Down's vines effecting the hive mind to alert the Demogoron.

-Adds gates the Demogorgon makes on the ground to traverse the dimensions.

-Adds a flashlight to see in the Upside Down.

-Adds redstone being effected by player presence in the Upside Down.

-Adds block culling to syncing, making the Upside Down remove lights, water and leaves seamlessly.

-Adds "no sync" mode where the Upside Down generates off a duplicate of the world seed and doesn't import chunks. (Gamerule)

-Adds "Season Five Generation" mode where the Upside Down will forcefully generate a 51x51 area or more as the only areas you can explore with the rest being blocked by a giant wall and a roof that resembles the Abyss. 

-Adds optional support for Immersive Portals where the player must break through the portal membrane to open it.

Update Two: Invasion of the Demodogs (Released!)

-Adds the Mind Flayer as the overarching antagonist that watches you and acts as the brain of the Upside Down.

-Adds Demodogs, adolescent Demogorgons that act as an invasion force to enter your world.

-Adds three opinion states the Mind Flayer can feel for you. THREAT which makes the Mind Flayer more likely to send hordes after you to try to kill you. VICTIM which makes the Mind Flayer take more of an interest in adding you to it's hive mind. And USEFUL which makes the Mind Flayer more likely to take control of you.

-Adds Mind Flayer awareness where the Mind Flayer can only mount attacks on players if it knows where they are. Being spotted by a flayed entity or stepping on a vine will cause the Mind Flayer to know where you are.

-Adds the "Flayed". A system where players or mobs can become spies for the Mind Flayer and do it's bidding.

-Adds the ability to save yourself, friends or mobs from being flayed by torturing the Mind Flayer out of them.

-Adds "true sight" where high Victim players will hallucinate the Mind Flayer.

-Adds a bunch of custom skybox animations where the Mind Flayer will menace the player by stalking them in the Upside Down should it be angry enough.

-Adds a tunnel system called the Underdark that dynamically grows under your world from a large cavern below Mothergates.

-Adds "growth points" to tunnels where they begin to spread an infection to your surface and create infected "Upperdark" areas. These can be burned away to cure the area. 

-Adds random ambushes by Demodogs that burrow from the tunnels to explore.

-Adds a Eleven's telekinetic powers with custom mechanics and combos to add a new dimension (not a literal one) to fighting.

-Adds telekinetic struggles where players fight with their minds.

-Adds Molotov Cocktails and Soul Molotov Cocktails to light the fire up in the Upside Down.

-Adds a second massive entrance to the Mothergate that acts as the source of the the blight on your world.

-Adds a minigame to seal the gate and destroy the blight on an area.

-Adds a brand new, original passive Upside Down originated creature known as a Flumph that just wants to be your friend! (And snitch on you...)

-Adds Demogorgon life stages and molting/growing behavior.

-Adds the ability to raise a Demo from infancy and domesticate it as your new best friend!

-Adds a decay system where overworld tools will become less effective in the Upside Down. (Delayed)

-Adds new makeshift weapons that can be crafted from bits and bobs in the Upside Down that do not decay. They're powerful but break faster, but are easy to repair. (Delayed)

-Adds Upside Down sickness where prolonged exposure to the atmosphere can be bad for your health.

-Adds slug "impregnation" where the Demogorgons use your live body to incubate it's young. (ew)

-Adds the Abyss that can be accessed by reaching the Upside Down's roof in Season 5 generation mode. Note this is just for fanservice and is a prototype so it will be pretty empty in this release.

Update Three: Night of the Living Flesh (Upcoming, plans still unconfirmed)

-Adds the Mind Flayer melting down creatures once it becomes angry enough at the player.

-Adds Meat Avatars the Mind Flayer will use sometimes in emergencies.

-Adds the mod's final boss, The Meat Flayer. A grotesque giant flesh avatar that will try to kill you or steal your powers if you have any.

-May add more custom mobs like the Thessalhydra/Tunnel Queen and some custom flesh monsters.

Update Four - Nightmare on the Block (Upcoming, plans still unconfirmed)

-Adds Demobats.

-Adds Demospiders (that will likely be configurable if you have arachnophobia.)

-Adds expanded Upside Down flora and fauna.

-Adds expanded psychic powers like mutations, ability strength, power granting and new powers.

-Adds the ability to ally with the Mind Flayer and become a "Litch". (Vecna)

-Adds the ability to enter the Void with Remote Viewing and stalk your friends or mobs.

-Adds Camazotz, a place where victims of Vecna are trapped during hallucinations.

-Adds the ability to curse players as Vecna and psychologically torture them until you use your powers to crush them and open a curse gate.

-Adds "Four Chimes" disaster where four curse gates merge and create a massive rift that decays at your world.

Update Five - The Flayed Crystal (Upcoming, plans still unconfirmed)

-Adds a proper flesh wall to the Upside Down.

-Adds a final dungeon to the Upside Down roof to properly unlock Eleven's powers. (Note you can get the powers in survival even in Update Two, but this would be the intended survival mechanic.)

-Adds "Sorcerer" (Will's) powers unlocked after being saved from being flayed. 

-Adds some more custom creatures.

MISC - Things that may just be added whenever

Suggestions for update mechanics can be sent in the suggestions channel on the Primrose Studios discord. If I think your idea fits, I will work it in.

New original creatures. I want to expand on the Upside Down's lore and worldbuilding to make it an actually compelling place to visit and make the danger of it worth it.

Biome specific fauna to the Upside Down.

"The Cult of the Arthrodomius" as a villainous cult of illagers and villagers who were trapped inside the Upside Down long ago and now worship the Mind Flayer as a god.

Any new ideas that are suggested by the team or players for lore and worldbuilding. (This mod's lore doesn't stricly adhere to Stranger Things and is going in it's own direction to maintain a cosmic horror vibe.)

A horde bossfight gamemode set in the Abyss with a custom final boss of the "Abyss" Mind Flayer spider form and Vecna. (For fanservice, I love y'all too much) 

Bikes! Some form of "rustic" hand-build bike would be cool and... you don't got Stranger Things without bikes.

Stuff I really don't wanna add:

Modern technology likes guns, flamethrowers or anything of the sort. This mod is asthetically based on a Vanilla+ style. So I'm sticking with low-tech stuff like Molotovs or Redstone. The ONLY exception is the flashlight, but I tried to make that feel like it's still redstone. 

NPCs of the characters. I still don't get why people want this... Do you just want Steve "the hair" Harrington to just randomly spawn in a forest somewhere? 

An NPC Vecna (outside of the final boss version for Horde Mode), Vecna is such a personal antagonist that I don't think I can do him much justice unless you play as him.

New ores, just no need for them. New resources from the Upside Down will have different functions.

An update related to Tales from 85. This is more of a maybe. I MAY include stuff from the show that fits the mod. But I don't think a comprehensive "Update Eighty-Five" or whatever will happen unless the show ends up being literally the coolest thing ever and everything it adds is cool that I literally cry from sheer peak.

The Abyss crashing to the Upside Down, this feels too permamnent of a thing to add as people will want a way to reverse it. I may add some way to lower the roof to simulate it.

Destroying the Upside Down, while I may add some kind of comsmetic Exotic Matter thing. A full way to destroy it is kind of counterintuitive to the mod's purpose. If I do add this in any form, it would be a fanservce thing and not a proper mechanic. 

A proper forge port, just use a connector bro. Future is now old man.

A bedrock port. Code wise, Bedrock is a completly different game from Java and I don't understamd how it works. I also don't care enough to bother.

Frequent version updates. Mojang keeps changing massive parts of Minecraft's code. If I was to keep updating the mod for new versions, I'd basically have to maintain multiple entire versions EVERY SINGLE time I want to update. I am one lady, I do not have the time for that.

KNOWN ISSUES:

-The Upside Down is NOT compatible with any world generation mod that alters the world height, removes features, adds features or adds modded blocks. The Upside Down generates based on the basic world seed and cannot read mods. This can be fixed by using Season 5 mode since in that mode, the Upside Down is ONLY synced chunks which do copy modded stuff properly. Note that the world height of the Upside Down is fixed so mods/packs that change that will likely not work.

-The Upside Down isn't compatible with shaders, use them if you wish. But they will break the intended effects. You can always modify them I guess, but I still don't reccomend it.

-The Upside Down doesn't work well with Distant Horizons due to DH removing the fog that makes the Upside Down so creepy.

-If you play an old world, you need to run it through the "optimize world" function Minecraft has or it wont sync properly. 

-Mothergate sometimes spawns weird, this is a product of Minecraft's generation engine.

-Performance can be a bit wonky. I will do what I can to fix it where I can.

COMPATABILITIES:

-Immersive Portals has official support but is not required. There are even some exclusive immersive features added when you use it. 

-Sodium, should be a given but there have been issues with this before. Also not required.

-Sinytra and Kilt connectors both work fine. Allowing crossplay between Forge and Fabric.

-World gen mods (when you're using S5 mode). 

-Dynamic Trees. (You'll need a connector for it, but it's super cool please try it.)

-Custom maps can be synced into the Upside Down with the command /initializeUpsideDown.

CREDITS AND SPECIAL THANKS:

(Most) 2D art assets by Unvalid.

3D assets, animations, sound design and Mind Flayer voice acting by Noelle.obj (Noelle Ossmann)

Inspiration for the vines implementation came from Beardielover's "Stranger Things Experience Mod".

Loananas for the Demogorgon's body model and texture.

Xcft for the bleeding effect's texture.

TheDoGGyS for the main menu logo.

.ganymedes__ for the floor gate's model.

N ess for the mothergate's model.

Jerica Joy Cade for providing the voice and concept of the Flumph.

Special thanks to Netflix, Stranger Things and the Duffer Bros for creating an amazing show and inspiring this project. It wouldn't be possible without them!

And you, for considering playing my silly little project.

Want to connect with me or other players of the mod? Join our Discord! 

This mod is being made by one amateur programmer and some help from friends, I can use all the help I can get. So if anyone wants to contribute programming help, animations or models, textures or anything at all. Please contact me on Discord through the server!