Submission #4933: jlun2's GBA Monster House in 05:52.32

Game Boy Advance
BizHawk 1.11.3
Monster House (USA) (En,Fr).gba
Submitted by jlun2 on 12/11/2015 10:59 PM
Submission Comments
I corrected some mistakes from the last TAS along with using new discoveries to save 18,371 frames.

Game objectives

  • Emulator used: BizHawk-1.11.3 VBA-Next core
  • Spawns objects
  • More off-screen action
  • Still no cheats used


I already knew the previous TAS had a bunch of errors, namely:
  1. Forgets to use the ledge at Basement 1 and ends up fighting the furnaces
  2. Uses DJ rather than Chowder during fights
  3. Too much backtracking; the furnace section after grabbing the dynamite could've been done without reloading the stage
  4. Doesn't use lua to keep track of off-screen events
I was initially hesitant to improve it given the reception for it being dull due to the off-screen glitches. My interest started after the Youtube user ""Luigi the Best" discovered a way tospawn objects out of bounds. Given that you can pretty much go OoB in almost every single floor by simply entering it and fall/drown while holding A+B, I immediately started the TAS.

Floor by Floor comments


I used the bios because the intro can be skipped with a reset. It is several frames faster to use a hard reset, if the bios was skipped. However, with the bios played, it ends up being slower. I included it since on console it's included, and therefore it would not be fair to "save" time solely because a hard reset on emulator doesn't play the bios.
And before anyone asks, a soft-reset it used this time.

First Floor

The lobby section is the same as before. This time, I enter Basement 1 using the carpet boss door so I can pull off an amazing glitch.

Basement 1

Pressing the button triggers the carpet cutscene. Normally it starts as soon as you enter the door, but since I skipped triggering the boss from the first floor, that does not happen. I get clipped into the garbage pile, and zip out of bounds.
From here, I move to coords ~10, ~10 (in Fixed Point 16.16) and pause the game to spawn a set of stairs to go back to the first floor.
This WIP was an old version where I spawned a block instead and zipped to the Furance stairs. I found an even better method however...

First Floor

I pause the game once to spawn a set of stairs back to Basement 1, but this time, at the same coords as the dynamite room.

Basement 1

I go downstairs and spawn at the dynamite room immediately. This time, I hop off the ledge off-screen rather than fight the furnaces.


In case anyone wonders why I couldn't simply spawn directly to the furnace boss, the reason was because it seemed to be a separate room; from my tries, attempting to "break in" to the boss chamber lead me stuck OoB.
This time, I don't backtrack to Basement 1, and immediately head to the boss. Once again, I thank "Luigi the Best" for finding out that auto-firing "B" allows you to walk through certain objects; that made the boss a LOT faster.
I found out Chowder is 37 frames faster than using DJ for this section. It seems every bubble has the same strength (8 iirc) just that charging shoots more at once. I recall this being twice as powerful than DJ's.

Basement 1

This time, I do the camera glitch earlier to avoid the bees.

First Floor

I enter the second floor instead so I could rush to the light. Also, dealing the final blow using Chowder is faster by ~10 frames than DJ all the way.



Every single address that's relevant to a 100% or any% TAS/run is in EWRAM (Replace "0x3DE7" with 02003DE7 for VBA). The above is relevant if anyone wants to tamper with the save file.


There are many ways to go out of bounds. Here are several:
  1. Delaying a cutscene that forces you to walk by pause and unpausing repeatedly and move next to a wall
  2. Hold A+B once you enter a new floor then without letting go drown or fall off a cliff/hole that doesn't send you to another floor.
  3. Rapid fire "B", move to the edges where only DJ can climb using Jenny or Chowder, then move to the other's position
  4. Falling off a cliff/hole or drown as soon as you enter a new floor (only possible if you spawned a set of stairs)
  5. Rapid fire "B" at the last boss
  6. During one of the 3 switch rooms, use the camera glitch to make one of the doors disappear, then walk through
If you get stuck in a wall, you'll zip at the opposite direction you hold (zip left holding right, etc).
The OoB areas appear glitchy at the edges of the map. Pausing and unpausing near there changes the camera focus on you, and potentially spawns objects (or change the ones that already exist). Also reentering the game area can sometimes mess with NPC hitboxes, causing them to move OoB towards you. I'm actually not sure how the objects are determined, just that if I don't pause, the stairs never seems to appear.
The stairs/holes outside the game area don't always appear to work right; often it makes you enter a new mostly empty floor but at the same coords.

Camera glitch

Pausing and unpausing before a room makes the objects unable to load, allowing you to bypass almost every obstacle. There are limitations:
  • Chests won't appear, since they're objects, so you can't always use this glitch to skip things
  • It doesn't work for very large rooms since by the time you reach the door, it's already loaded. Pretty much why Basement 1 route is like that in the TAS
  • It won't work for very small rooms, since you can't move far enough to reload the entrance
  • Certain types of entrances such as the room to the arcade machine, the other basement door in the lobby, and the furnace boss door don't work
  • Any flags for that room will not work, so if there's something that needs to be triggered you can't use this glitch


  • For Jenny at least, you can rush forward once every 26 frames
  • Rush by holding a direction for 2 frames, nothing for 2 frames, then said direction again for 3 frames
  • I have no idea what the health of NPC's are; I know it exists, but either it has some strange format or it's not in EWRAM
  • I also have no clue how to get 100%, so please don't discuss about what tricks should be used or not unless a way to get more than 97% total is found
  • In case anyone wonders why I didn't grab a candy right after the furnace, it's because when I tried doing so the same time as the cutscene begins, the game resets
  • I could've technically skipped the credits by pressing "A", but since I can't skip the dialogue before the credits, I decide not to.
  • The lua script I used is in this post. The address for the coords are only approximates; they fail at far out of bounds edges of the map and in certain rooms like the arcade machine room.

Other comments

Suggested screenshot

Frame 3998

Potential improvements

  1. Find a way to spawn the credits
  2. Or at least break into the boss chamber
  3. Find out how OoB objects work in general and the limits

jlun2: Found that I messed up a large part of the input. Sorry!
Noxxa: Replaced submission file with a 772-frame improvement.

ars4326: Judging!
ars4326: Hi again, jlun2. Very nice improvement over your prior TAS! In particular, the much shortened Furnace Boss fight was especially of note, along with the various discoveries and optimizations made toward the OoB glitches. Good technical work, overall :)
Accepting as an improvement to the published run!
fsvgm777: Processing.
Last Edited by adelikat on 10/15/2023 1:15 AM
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