Difference between revisions of "Dungeon ID swapping"

From ALttPR Wiki
Jump to: navigation, search
(2. Pass through the sewer/throne door)
 
Line 1: Line 1:
In vanilla ALttP, [[Hyrule Castle]] and the [[Sewers]] are considered different dungeons. When you pass through the door between the throne room and the sewers, the game changes the ID of the dungeon you're in by XORing it with 2. This is a symmetrical operation, so it creates pairs of dungeons you can swap between if your dungeon ID is not actually Hyrule Castle.
+
In vanilla ALttP, [[Hyrule Castle]] and the [[Sewers]] are considered different dungeons. When you pass through the door between the [[throne room]] and the [[sewers]], the game changes the ID of the dungeon you're in by XORing it with 2. This is a symmetrical operation, so it creates pairs of dungeons you can swap between if your dungeon ID is not actually [[Hyrule Castle]].
  
Dungeon ID swapping can allow you to collect the prize (crystal or pendant) of a dungeon without ever entering it. It's important as a way to complete {{nl|Misery Mire}} in No Logic without having the correct medallion for it.
+
Dungeon ID swapping can allow you to collect the [[prize]] ([[crystal]] or [[pendant]]) of a dungeon without ever entering it. It's important as a way to complete {{nl|Misery Mire}} in [[No Logic]] without having the correct [[medallion]] for it.
  
 
{| class="wikitable"
 
{| class="wikitable"
Line 27: Line 27:
 
If you're in [[cave state]], the dungeon ID becomes <tt>$FD</tt>, which is an alternate cave state in the vanilla game, and crashes in the randomizer.
 
If you're in [[cave state]], the dungeon ID becomes <tt>$FD</tt>, which is an alternate cave state in the vanilla game, and crashes in the randomizer.
  
Almost all setups for dungeon ID swapping (besides playing Hyrule Castle as intended) need to come from the sewers and go back and forth through the throne, so you need to do [[sewer door deletion]] first.
+
Almost all setups for dungeon ID swapping (besides playing [[Hyrule Castle]] as intended) need to come from the [[sewers]] and go back and forth through the [[throne]], so you need to do [[sewer door deletion]] first.
  
 
== The usual route ==
 
== The usual route ==
  
[[Image:dungeon-swap.png|thumb|right|384px|A diagram of the dungeon-swapping route that starts and ends in Hera]]
+
[[Image:dungeon-swap.png|thumb|right|384px|A diagram of the dungeon-swapping route that starts and ends in [[Hera]]]]
  
 
Keep in mind the prerequisites to dungeon ID swapping:
 
Keep in mind the prerequisites to dungeon ID swapping:
  
* You must have performed [[sewer door deletion]] at some point or be able to [[hookpush]]. Remmeber that the result of sewer door deletion gets saved, so it can be any time earlier in your run.
+
* You must have performed [[sewer door deletion]] at some point or be able to [[hookpush]]. Remember that the result of [[sewer door deletion]] gets saved, so it can be any time earlier in your run.
* This route starts and ends in the {{nl|Tower of Hera}}. Assuming the dungeon ID you want to swap isn't Tower of Hera, you need to get into Hera from a different dungeon, which fortunately there are many ways to do. For example, if you want to swap from {{nl|Palace of Darkness}} to {{nl|Misery Mire}}, start by performing a [[YBA]] from PoD to Hera.
+
* This route starts and ends in the {{nl|Tower of Hera}}. Assuming the dungeon ID you want to swap isn't [[Tower of Hera]], you need to get into [[Hera]] from a different dungeon, which fortunately there are many ways to do. For example, if you want to swap from {{nl|Palace of Darkness}} to {{nl|Misery Mire}}, start by performing a [[YBA]] from [[PoD]] to [[Hera]].
 
* The last step is in a dark room, so it will be hard to do if you don't have a [[Lamp]].
 
* The last step is in a dark room, so it will be hard to do if you don't have a [[Lamp]].
  
 
More images of the steps appear in [https://imgur.com/a/SuW7Jt9 this imgur post].
 
More images of the steps appear in [https://imgur.com/a/SuW7Jt9 this imgur post].
  
=== 1. Bomb clip from Hera to the sewer ===
+
=== 1. [[Bomb clip]] from [[Hera]] to the [[sewer]] ===
  
* In the southeast room of Hera 3F, place a bomb to the upper right of the crystal switch.
+
* In the southeast room of [[Hera]] 3F, place a [[bomb]] to the upper right of the [[crystal switch]].
* Dash rightward along the slope into the bomb, and hold up+left during the knockback.
+
* Dash rightward along the slope into the [[bomb]], and hold {{B|^<}} during the knockback.
* You clip through the slope into the dark sewer.
+
* You clip through the slope into the [[dark sewer]].
  
[[Image:Hera-to-sewer.png|frame|none|Line up against the top edge of the switch, with your shadow centered on the vertical edge between tiles, and place a bomb.]]
+
[[Image:Hera-to-sewer.png|frame|none|Line up against the top edge of the [[crystal switch]], with your shadow centered on the vertical edge between tiles, and place a [[bomb]].]]
  
 
=== 2. Pass through the sewer/throne door ===
 
=== 2. Pass through the sewer/throne door ===
  
If you have performed [[sewer door deletion]], the shutter door at the south end of this room isn't really there anymore. Go through it into the throne room, then go back through it into the sewer.
+
If you have performed [[sewer door deletion]], the shutter door at the south end of this room isn't really there anymore. Go through it into the [[throne room]], then go back through it into the [[sewer]].
  
 
Alternative, you can [[hookpush]] thought the wall with the closed door.
 
Alternative, you can [[hookpush]] thought the wall with the closed door.
Line 63: Line 63:
 
This is the moment that your dungeon ID swaps. If you have a compass and dungeon counters are on, you may see the dungeon counter change.
 
This is the moment that your dungeon ID swaps. If you have a compass and dungeon counters are on, you may see the dungeon counter change.
  
=== 3. Proceed through the sewers ===
+
=== 3. Proceed through the [[sewers]] ===
  
Play the game normally until you get to the key-rat room.
+
Play the game normally until you get to the [[key-rat]] room.
  
=== 4. YBA/Hookpush to get back into Hera ===
+
=== 4. [[YBA]]/[[Hookpush]] to get back into [[Hera]] ===
  
 
From the key-rat room:
 
From the key-rat room:
Line 75: Line 75:
 
* Pass through the door, and emerge from the top wall of Hera 3F.
 
* Pass through the door, and emerge from the top wall of Hera 3F.
  
Sprites (such as enemies) are likely to despawn in this step. If Moldorm is already defeated, you can head to the top floor to claim your dungeon prize.
+
Sprites (such as enemies) are likely to despawn in this step. If [[Moldorm]] is already defeated, you can head to the top floor to claim your [[dungeon prize]].
  
Alternative, you can [[hookpush]] thought the wall with the closed door and you can go back to Hera.
+
Alternative, you can [[hookpush]] thought the wall with the closed door and you can go back to [[Hera]].
  
 
{| class="wikitable"
 
{| class="wikitable"

Latest revision as of 00:16, 2 May 2022

In vanilla ALttP, Hyrule Castle and the Sewers are considered different dungeons. When you pass through the door between the throne room and the sewers, the game changes the ID of the dungeon you're in by XORing it with 2. This is a symmetrical operation, so it creates pairs of dungeons you can swap between if your dungeon ID is not actually Hyrule Castle.

Dungeon ID swapping can allow you to collect the prize (crystal or pendant) of a dungeon without ever entering it. It's important as a way to complete Misery Mire (NL) in No Logic without having the correct medallion for it.

Dungeon IDs that can be swapped with each other
Dungeon 1 Dungeon 2
Hyrule Castle Sewers
Eastern Palace Desert Palace
Tower of Hera Thieves' Town
Hyrule Castle Tower Swamp Palace
Palace of Darkness Misery Mire
Skull Woods Ice Palace
Turtle Rock Ganon's Tower

(links are to the No Logic guides for these dungeons)

If you're in cave state, the dungeon ID becomes $FD, which is an alternate cave state in the vanilla game, and crashes in the randomizer.

Almost all setups for dungeon ID swapping (besides playing Hyrule Castle as intended) need to come from the sewers and go back and forth through the throne, so you need to do sewer door deletion first.

The usual route

A diagram of the dungeon-swapping route that starts and ends in Hera

Keep in mind the prerequisites to dungeon ID swapping:

More images of the steps appear in this imgur post.

1. Bomb clip from Hera to the sewer

  • In the southeast room of Hera 3F, place a bomb to the upper right of the crystal switch.
  • Dash rightward along the slope into the bomb, and hold ^< during the knockback.
  • You clip through the slope into the dark sewer.
Line up against the top edge of the crystal switch, with your shadow centered on the vertical edge between tiles, and place a bomb.

2. Pass through the sewer/throne door

If you have performed sewer door deletion, the shutter door at the south end of this room isn't really there anymore. Go through it into the throne room, then go back through it into the sewer.

Alternative, you can hookpush thought the wall with the closed door.

Lit room in practice hack
HP-IDswap.gif

This is the moment that your dungeon ID swaps. If you have a compass and dungeon counters are on, you may see the dungeon counter change.

3. Proceed through the sewers

Play the game normally until you get to the key-rat room.

4. YBA/Hookpush to get back into Hera

From the key-rat room:

  • Do a south subtile YBA (drinking a red or green potion at the moment you go through the door)
  • Tap left or right about 5 times, to back out at least 5 pixels while staying in the door.
  • Pass through the door, and emerge from the top wall of Hera 3F.

Sprites (such as enemies) are likely to despawn in this step. If Moldorm is already defeated, you can head to the top floor to claim your dungeon prize.

Alternative, you can hookpush thought the wall with the closed door and you can go back to Hera.

Lit room in practice hack
HP-IDswap2.gif