Bomb Trigger

Discovered by GreenTunic

Bomb Triggers allow Link to trigger certain cutscenes or item grabs with the use of two bombs. It significantly saves time in both LA and LADX runs, as it is used to essentially skip the Ocarina - among other things.

BTs work on all versions of Link's Awakening, but they do not work on the 1.1 and 1.2 versions of Link's Awakening DX.

Mechanics

When Link drops a bomb or shoots an arrow, a timer will begin counting down from six - subtracting by one each frame until the timer finally hits zero. This timer can be pause by bringing up any menu. If Link drops either projectile when this timer is greater than zero, then the game will execute the bomb-arrow code - which is designed to turn an arrow into a bomb-arrow. However, this code does not explicitly check whether or not either of the projectiles are an arrow (unless you're playing on LADX v1.1 or v1.2). Because of this, if Link drops two bomb within this window, the game manipulates a few variables - one being a variable that controls cutscene states for the entity in the first sprite slot.

Link can usually only drop one bomb at a time, which is probably why the developers didn't fix the code until much later. However, there are a few ways of despawning a bomb which BTs exploit.

You'll notice that, although the frame window for bomb-arrows is six frames, BTs only work within a four frame window. This is because of two things: first being that you cannot drop two bombs on two consecutive frames (otherwise you'd simply be holding the bomb button for two frames); second being that BTs do not work when the timer has one frame remaining - the reason for which is unknown.

Bomb Triggering out of a screen transition

For some unknown reason, BTs do not work if you've shot an arrow at any moment before performing the trick. Luckily this is only temporary, and can be reversed by warping (using a door/staircase/S&Qing). Likewise, because BTs manipulate the cutscene state for only the sprite in the first sprite slot, often times it will be required to kill a specific enemy before doing the trick.

Unbuffered

  1. Equip bombs beforehand
  2. Line up with the screen transition.
  3. If you're doing a vertical screen transition, press or down and the bomb button at the same time. If you're doing a horizontal screen transition, make sure Link is facing up or down, and then press up+left/right and the bomb input at the same time
  4. Hold the bomb button throughout the entire screen transition.

If done successfully, you should see an explosion happen for a fraction of a second, however you will not hear an explosion sound.

Lining up with the screen transition can be easily done by either jumping against the boundary or curving a bonk into it.

Buffered (LADX)

Failure of the unbuffered method often happens because the bomb or directional are not being pressed on the same frame.

  • If Link keeps dropping a bomb before the transition but not after, try buffering a pause out of the transition and then use the pause menu to buffer the second bomb.
  • If Link is not dropping the first bomb, then try pausing and then buffering the directional + bomb inputs

Even when buffered, BTs out of horizontal transitions can still fail. This is because of a bad sub-pixel alignment which has a 25% chance of occuring during gameplay.

Buffered (LA)

In LA, there is only one way to buffer screen transition BTs. This is because the pause menu can only buffer directionals and a few items.

  1. Equip bombs beforehand
  2. Line up with the screen transition
  3. Drop a bomb and pause immediately after.
  4. Unpause and hold whatever directional you need to hold so that Link transitions
  5. During the transition, hold the bomb button

Failure often results because the pause menu was brought up too late. Try pressing the bomb button and the pause button at the same time, delaying the pause input only slightly.

Advanced Unbuffered Method

Because BTs can happen within a certain frame gap, there is a small distance away from the screen transtion where Link can drop the first bomb and still be able to BT post transition. This method is very difficult as it requires the player to release the first bomb input before transitioning in order to buffer the second input during the transition. Likewise, Link has to begin transitioning within four frames of dropping the first bomb in order for the BT to happen. On LADX, often times runners will buffer a pause out of the transition, only to use the pause to buffer the second bomb input which makes this method much easier.

Here are all the positions that work relative to the screen boundary:

Upwards BT Positions
3px away2px away1px away0px away (standard)
Upwards BT, 3px awayUpwards BT, 2px awayUpwards BT, 1px awayUpwards BT, 0px away
Downwards BT Positions
3px away2px away1px away0px away (standard)
Downwards BT, 3px awayDownwards BT, 2px awayDownwards BT, 1px awayDownwards BT, 0px away
Leftwards BT Positions
2px away1px away0px away (standard)
Leftwards BT, 2px awayLeftwards BT, 1px awayLeftwards BT, 0px away
Rightwards BT Positions
2px away1px away0px away (standard)
Rightwards BT, 2px awayRightwards BT, 1px awayRightwards BT, 0px away

Pit Bomb Triggers

Pit BTs are quite simple, however quite difficult to execute. Drop a bomb in a pit (so it instantly falls) then you have 4 frames to drop another bomb, which will cause the trigger to happen. Luckily the second Bomb input can be buffered in much the same way LA buffered screen transition BTs are done.

Dropping bombs on certain tiles in side-scroller rooms can cause them to begin falling as if they were dropped into a pit. This means that Pit BTs can be done in some side-scroller rooms as well, namely the Seashell Mansion and the Fisherman's Hideout.

Off-screen Bomb Triggers

Discovered by GreenTunic

Dropping a bomb off screen causes it to instantly despawn, and typically Link is only off screen after some sort of warp sequence. Because of this, performing an off-screen bomb trigger is as simple as mashing the bomb button as fast as you can while Link is off screen.

Last updated 07/15/2018 – Rapid_