Exploration Glitch

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Exploration glitches are a set of glitches that enable Link to enter a special layer that allows him to move through walls.

Link is "under" the room, and will be mostly stuck in this layer, but there are some rooms where you can exit this layer to get back into the "normal" game.

Since most of the underworld screens are actually located on one map, this glitch will allow Link to travel between many of the indoor rooms in the game very quickly. See the EG Map page for additional info.

This glitch can be used to finish the game in under 2 minutes in the Any% category.

How to perform it

There are several methods for entering the EG layer:

  • Arming EG by S+Q during a jump while indoors (see below)
  • Arming EG via Mirror Jumps (the indoor type)
  • Arming EG through jumping into a Void
  • Clipping
  • Door Glitches into certain rooms
  • Certain types of Hookpush

Technical explanation

Green = Strong EG
Orange = Weak EG
Yellow = Kick
Black = Dark room

EG is caused by triggering an indoor layer transition in an unintended manner. With clipping (see Clipping ), the player can maneuver out of bounds until either a normally unreachable ledgehop can be accessed or a ledgehop is accessed from an incorrect direction, allowing the player to enter EG.

There are 3 ways EG can be "armed." This is the result of interrupting an indoor ledgehop, which stores a layer change in the game's memory. Through taking damage or bonking, this layer change can be activated elsewhere, leading to EG. The 3 ways to arm EG are:

  1. Jump S&Q: Saving and quitting the game while in the middle of an indoor ledgehop. The stored layer change persists in the game's memory through a save & quit.
  2. Indoor Mirror Jumps: Using the Mirror at the same Link hops a ledge.
  3. Void Arming: Jumping into a void. The game generally prevents this from being possible in normal gameplay, but if you get out-of-bounds or into EG, you can access many voids from ledgehops, which will arm EG.

With armed EG, it will be disarmed if the player uses any indoor ledgehops or any north ledgehops on the overworld. It will also be disarmed if the player tries to enter EG with damage or bonking while having Weak EG set (see EG Strength below). If the player has EG armed and takes damage or bonks on the overworld, then Link will enter an Overworld EG state, which is considered a separate glitch by the community.

EG Strength

When using armed EG, it may be important to understand EG Strength. Each supertile in the underworld sets a value in memory related to the layering effects of the game. This can sometimes prevent the player from using stored EG to enter the EG layer.

On the map shown, entering supertiles colored green will give Strong EG, allowing the player to use armed EG to enter EG. Supertiles colored orange will give Weak EG, and players cannot activate armed EG in these rooms. Unmarked rooms do not update the value in memory, meaning that if you want to activate armed EG in one of these rooms, you must be sure that the last time the value was set, it was from a supertile marked as strong. Rooms marked in yellow will kick Link out of EG. This is caused either by moving walls or dynamic conveyor belts. For moving wall rooms, moving the wall will turn the room into one that does not affect EG.

Exiting EG

There are a few ways to exit the EG layer if the player wishes to do so:

  1. The most common way is to use "high" walls, often (but not always) found in layered rooms (Supertiles that set Strong EG), to jump back in-bounds.
  2. \ / Auto Stairs (that is stairs where the upper layer is at the top of the stairs, and the lower layer is oriented at the bottom) in rooms that set Strong EG can be used to get in-bounds. Link is able to use them from above even while in EG, which will place him in-bounds on the lower layer.
  3. Spiral stair doors that are on the lower layer of a layered room (Supertiles that set Strong EG) can be used while in EG. Link will transition and in the next room, he will be in-bounds.
  4. EG Kick by visiting Supertiles with dynamic conveyor floors or moving walls.
  5. Weirdshot

Overworld EG

EG functions exactly the same on the overworld, with the major difference being that the overworld only has 1 layer. Overworld maps contain more collision than underworld rooms, so they also use a different calculation. These two factors combined mean that collision is only coded to check for 1 layer, so EG cannot be used on the overworld to bypass tile collision. It does, however, put Link on a different layer from sprites, allowing him to ignore collision with them, including barriers like the Desert monuments or the Lumberjacks' tree. Any sprite spawned from a bush will inherit Link's layer.

Link will not be visible most of the time because he is drawn behind background layer 2, which contains the entirety of the overworld map's graphics. He can be seen when passing under tiles that have transparency, though, such as tree roots.