Exploration Glitch

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Revision as of 20:48, 15 July 2018 by Kan (talk | contribs) (Technical explanation)
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Summary

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 This map (image) or This map (interactive map) to see how the underworld screens are connected.

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:

Semi-EG

A form of EG that includes wrong warps, door rewriting, YBA, Mirror or Somaria Block screen scrolling, pulling statues through doors.

helge: This is just the same text we have on Categories . Would be nice if someone who knows about this stuff could write about it in more detail.

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. With indoor Mirror Jumps, a layer transition is stored after the mirror jump and can be activated by later taking damage or bonking. S&Q EG arming is similar. If the player save and quits while Link is in the air from a ledgehop, EG will be armed after the save and quit.

If EG is armed from a S&Q or Mirror Jump, it will be disarmed if the player uses any indoor ledge hops 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. Unfortunately overworld EG has limited utility as Link still interacts with the map's boundaries (unlike underworld EG). However, Link cannot interact with enemies and sprites while in overworld EG.

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. The most common way is to use "high" walls, often found in layered rooms, to jump back in-bounds. Another way is to use particular sets of underworld stairs (insert picture). These will bring Link back in-bounds if used from above. The final method is to enter supertiles that have dynamic conveyor floors or moving walls in any of the rooms. In these tiles, Link will be immediately popped out of EG upon entering such rooms.

Applications

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