Fake Worlds

A fake world is a glitched state where the screen Link is on belongs to a different world than what the game's current world flag indicates. This conflict has a number of important consequences for glitched speedruns.

Explanation

Link's world is controlled by the value at memory address $0FFF, which we'll call the world flag. In normal gameplay, the value at this address agrees with where Link physically is. However, through various glitched means, players can get Link to be on a screen belonging to the opposite world from what's indicated by the world flag. If he's on a Dark World screen, but the world flag is set to Light World, the community calls this fake Dark World. And if he's on a Light World screen, but the world flag is set to Dark World, we call this being in fake Light World.

Methods for being in a fake world

There are a few different ways to get into a fake world state:

• Clipping, using transition corruptions, or EGing to travel from a cave/dungeon room in one world to a cave/dungeon room in the opposite world. Because all indoor rooms in the game share the same map, you can, for example, glitch from a Light World cave into a Dark World dungeon. Because Link never warped between worlds, the game's world flag still thinks of him as being in Light World, even though he's in a Dark World area. Kiki Skip is an example of this exact scenario.
• Dying in a Dark World dungeon prior to defeating Agahnim1. When Link dies in the Dark World before defeating Agahnim1, he is immediately put in Light World. The game does this because you can theoretically die on Dark Death Mountain before fighting Agahnim, and if the game treated this normally, Link would be placed on the Pyramid for a massive sequence break. Through using glitches, the entire Dark World is easily accessed before defeating Agahnim1. Dying on the overworld will simply place Link in the Light World and give the player the selection of standard Light World spawn points. But if Link dies in a Dark World dungeon, he'll be placed back at the entrance to the dungeon but with the world flag swapped over to Light World, thus being in fake Dark World.
• Fake fluting while on the Dark World overworld. The flute is never supposed to be used in the Dark World, but it can be done using a fake flute. The screen the bird takes Link to will be a Light World overworld screen, but because Link never warped, the world flag is still set to Dark World. So the player will be in a fake Light World state.

Effects of fake worlds

Fake world states have a few significant consequences, some of which may help the player and make certain glitch speedrun routes possible. But there are also consequences with potentially dire effects the player may need to pay attention to.

Link state

If the player is in fake Dark World, they will be normal Link instead of a bunny, even if Link doesn't have the moon pearl in his inventory. This is one of the most beneficial consequences of fake worlds, as in many RMG and MG speedrun routes, it can be faster to do some Dark World content prior to collecting the moon pearl.

Fake world behavior on the overworld

While on a fake world overworld screen, all normal sprites (NPCs, enemies, etc.) and underworld entrances on that screen will be there as expected, but as soon as the player triggers an overworld screen transition, the game will load the proper world based on what the world flag is set to.

So for example, let's say the player glitches from a Light World dungeon, house, or cave and travels to Thieves' Town. They exit Thieves' out of its front door onto the Village of Outcasts screen. All the normal enemies and NPCs will be there, and the player can freely enter the C-shaped house, brewery, or chest game if they wish. But if the player transitions south, the screen with the library will load not the screen with the frog and the arrow-shooting minigame. After transitioning like this, the player is just in full true Light World. This can be good or bad depending on context. If the player wants to be in the true world (the one the world flag is set to), it can save warp time to just transition. But if the player wants to stay in the world opposite the world flag, transitioning can lose a lot of time, especially if the player transitions to the Light World when they want to be in the Dark World. In that case, the player will have to find a warp back to the Dark World, and the mirror won't do it.

Mirroring in fake Dark World

While on a fake Dark World overworld screen, Link can use the mirror, and he'll warp to the real Dark World. This is different from normal gameplay, where Link is unable to use the mirror to warp to the Dark World.

This can be used as part of a route, or it can be used as a backup if the player is ever unintentionally in fake Dark World and needs to be in the real one (ie. for using overworld transitions).

Sprite and scenery differences

Sometimes the world flag may be used to vary sprite graphics, behavior, or scenery.

One example of this is that the graphics used by pots will match the world indicated by the world flag. In normal gameplay, you will see the clay pots in Light World areas and the skull-shaped pots in Dark World areas. But in a fake Dark World, you'll see clay pots in Dark World areas, and in fake Light World, you'll see skull-shaped pots in Light World areas. This is a purely aesthetic thing, but it can be a signal to the player about what world state they're in.

A more practical example with real effects: the crickets in the attic of Thieves' Town are the exact same sprite by ID as rats are. The game uses the world to vary their behavior. If the player visits the Thieves' attic in a Light World state, the crickets will squeak like rats and, more importantly, they'll only deal 1/4 heart damage instead of a full 2 hearts (assuming Link is wearing the green tunic).

Dungeon prize conflicts

Fake worlds can create dungeon prize conflicts. This can be important to pay attention to in RMG/MG speedruns that are finishing a dungeon while in a fake world state. Under certain conditions, the prize from the dungeon (the pendant or the crystal) won't spawn, and Link will just be stuck in the boss room with no way to progress.

Explanation

Due to the way boss rooms determine which item to drop, fake worlds check the opposite set of flags; i.e. fake Dark World looks at pendants, and fake Light World looks at crystals. Grabbing the prize always results in the correct flags being set, but the check makes certain pendant-crystal pairs shadow each other, preventing the fake world prize from dropping.

The three pairs that have the shadowing are:

• Palace of Darkness and Desert Palace
• Ice Palace and Eastern Palace
• Misery Mire and Tower of Hera

Implications

Consider the following situation:

• A runner is playing a glitched category that defeats Agahnim1 late in the run, and they haven't defeated him yet.
• They've already beaten Eastern Palace and collected the green pendant.
• While doing Ice Palace, they die to Kholdstare.

Because they've died in the Dark World before defeating Agahnim1, they'll be in fake Dark World. If they just go through Ice Palace again and fight Kholdstare without fixing this, the crystal won't drop after Kholdstare is defeated. This is because their world flag indicates that Link is in Light World, and they've received the Eastern Palace prize already, which will "shadow" the Ice Palace prize when Link is in Light World.

To fix this, the player must leave the dungeon and use the mirror on the overworld. The game will allow Link to mirror to Dark World on a fake Dark World screen.