I'm just trying to gather some info in one place about this game and its tricks and glitches and fun things. I'll update this with clips and videos and more info as time passes. You can find out more by looking at these links:
This guide is written and maintained by NullSprite.
Note: We need videos and clips for pretty much everything. We'll update as fast as we have it all.
Donkey Kong for the Gameboy is a fun, fast-paced Mario platformer for the Gameboy. It has SGB enhancements (colors, custom frame, sounds and music) even though most speedrunners play it using Gameboy emulators.
You need a computer and a proper Gameboy emulator. You can use either Gambatte or BGB for this, but Gambatte is recommended if you're looking to do some of the glitches. Note that the Gambatte core used for RetroArch or RetroPie is inaccurate and should not be used for speedrunning.
There are two versions of the game: 1.0 and 1.1, which have a few differences. 1.0 will let you do the IFG in 5-6 for the All Stages category, while 1.1 will let you do the file copy glitch in 5-5 for the Beat The Game category. Unless you're running Beat The Game, you'll want the 1.0 version of the game.
Pick whatever is most comfortable for you. ¯\_(ツ)_/¯
Difficulty level: Easy
Used in: Lots and lots of stages
Walljumping is not something the game means for you to do, but it can be accomplished much like in other platformer games of the era (such as Super Mario Bros. 3 or Super Mario World.) Walljumps can only be performed on the left side of a wall with Mario facing right (except in some extraordinary cases) There are two common ways to do this:
- Backflipping into the wall, then jumping from the wall. This requires Mario to backflip into the wall from a certain distance, then jumping again at the right time as he hits the edge of the wall within a three-frame window. After backflipping, you will know if you can get the walljump by seeing if Mario turns to the right. This requires a good deal of practice and a lot of patience, but once you develop a feel for it, it's quite easy to get.
- Handspring jumping into the wall, then jumping from the wall. PTO1 recently discovered that if you run into the wall, keep holding right or right+down and perform a handspring jump against the wall, it's very easy to get the walljump. You still have to hit the jump off the wall at the right frame window, but this is generally more consistent than using the backflip.
Difficulty level: Medium
Used in: 2-1, 2-2, 5-7, 5-9, 6-7, 8-5, 8-7, 8-9
The key glitch is executed by grabbing the key while backflipping, then jumping off a ledge and tumbling on the ground. This will make the key "stick" in its vertical position, and Mario will not be able to jump or throw the key away until he re-grabs the key after a few seconds. While in this phase, Mario is invulnerable to any damage. If Mario tumbles again while in this phase, the key will stick in both the horizontal and vertical position it was in when Mario performed the second tumble. After this, Mario will be able to move freely as if he did not have the key, but taking Mario to the door will result in the stage finishing.
Difficulty level: Easy
Used in: 3-6, 4-1, 4-5, 6-1, 8-10
Basejumping can be accomplished by grabbing the key while backflipping, then jumping off a ledge. While Mario is in the air, he will not drop the key in this state as he normally does, and if Mario lands by the door the stage will finish, even if Mario would normally die from fall damage. This can be used to quickly traverse vertical levels quickly.
Difficulty level: Medium+
Used in: 3-3, 7-4, 8-6
Clipping is generally not a very common thing in DK94, but it is possible to clip vertically through blocks due to how ejection works. Mario cannot perform clips like these on his own, but instead needs something to push him, such as a Kurassha (falling blocks), a spring or an enemy such as a Sir Shovalot. There are few cases where clipping is advisable as Mario can get stuck easily with no way to get out.
Difficulty level: Medium+
Used in: 2-12, 4-3, 7-11 (backup strat)
Extended handspring jumps are performed by handspring jumping off a spring, while hitting and holding A at the right time. This allows Mario to gain extra height in his jump so he can reach places he normally wouldn't be able to, and can also serve as a fast way of getting into a handstand after jumping off the spring.
Difficulty level: Hard
Used in: 5-6
IFG is a trick which is notorious for ending runs, and currently is only usable in 5-6 to save ~15s compared to the normal strat. This is accomplished by having Mario jump left into a gap that is one tile large vertically, then holding left. After some time, the value that keeps track of how far Mario has fallen overflows and starts interrupting normal RAM behavior. At this point, letting go of left at the right time will make Mario tumble and the stage will end, skipping normal animations.
There are generally two things that can go wrong:
- You can mess up the glitch in the stage itself, which will usually make the game halt, reboot or simply glitch out beyond repair.
- You can seemingly get the glitch and finish the stage, but there is still a chance that the game might reset in the cutscene after 5-8. Since the game resets before you can save, this means you have to play the game from 5-5 over again.
This trick requires a lot of practice and is generally not considered to be a very safe trick as it can mess with your save files. Do not attempt this glitch without having a backup of your save files!
Difficulty level: Easy
Used in: 5-9, 5-10, 8-15
The way ejection works in the game makes it so that any item Mario throws into a wall of solid blocks will be ejected upwards and to the right. This can be used to transport the key easily to areas of stages that would normally not be reachable, most notably the tall wall in 5-10.
Difficulty level: Normal
Used in: The whole game, mostly
RNG manipulation for DK94 is achieved through hard resetting the game at certain points, usually after finishing a world. The reason we started resetting after finishing a world is because it saves time over watching the "blinking transition", but the side effect of hard resetting is that the RNG resets to a known state.
As the game boots up, the RNG is set to its initial state. The animation in the opening cutscene where DK smashes the brick wall actually changes the RNG a lot (over 50 times!), but once the bricks have been cleared from the screen and DK's eyes show up, the RNG stops changing. This means we can start the game with one of two RNG values consistently: "first seed" which is the one you get before the brick smashing animation, and "last seed" which is the one you get after the animation is over.
The RNG for the game is programmed in such a way that whenever something accesses the RNG to use the value for something, it also changes that value. By tracking the number of changes to the RNG, we can predict how the game will position and move enemies, how boss fights will play out and mostly how elements on the stage will function. Most enemies do not require RNG values after they have been spawned, but some enemies such as the fireballs and Snapjaws use RNG a lot to determine how they should move around and which paths they should take. It is recommended that you use Bizhawk's RAM inspector to see how the RNG changes in different stages; the RNG value for the game is stored in a 2U integer at memory address 0xDEFE.
At present time, the following RNG manipulation route is mostly used by all runners:
- Starting the game: last seed
- After resetting after world 1: first seed
- After resetting after world 2: first seed
- After resetting after world 3: last seed
- After resetting after world 4: first seed
- After resetting after world 5: first seed
- After resetting after world 6: first seed
- After resetting after world 7: first seed
- After resetting after 8-12: first seed
- After resetting after world 8: last seed
- After resetting after 9-4: first seed
Difficulty level: Medium
Used in: 8-16
In 8-16, there is a way to go out of bounds and position Mario at a certain point to make the boss stage end without hitting DK.
- You will need to reset after the cutscene after 8-12, otherwise the glitch will not work.
- When starting 8-16, backflip up to the level where DK is standing, then handspring jump up into Pauline. This will eject Mario upwards.
- Once Mario finishes his handspring jump, press and hold right. If Mario was ejected high enough upwards, the stage will end shortly after this.
Difficulty level: Easy
Used in: 3-2
There is a trick that can let Mario duplicate items, most notably the key, and some enemies. This is achieved by grabbing an item or enemy while backflipping, jumping off a ledge and then pressing B as Mario lands and tumbles. This makes Mario re-grab the item he was holding, but the side effect of this is that the game actually makes a copy of whatever that item was. Since the game doesn't exactly know how to deal with this, it can result in very severe glitching that can halt the game or even delete or alter save files. The trick is, however, used in 3-2 to quickly re-grab the key after tumbling down, but nothing is done with the duplicate item.
Use this glitch with caution. It has been known to do things that are, well, not good.
Difficulty level: are you actually insane wtf are you doing
Used in: 5-5, 9-9
Note: the documentation of this glitch is still in the works.
The file duplication glitch is used for the Beat The Game category and is not viable for any other category.
It has been discovered that the Item Duplication Glitch, when performed correctly in 5-5, will let you copy the file progress from one file to a new file when playing on version 1.1. This is the common way of playing the Beat The Game category.
It was also recently discovered that it is possible to use this glitch while playing in 9-9, but there have been no runs that have gotten this glitch yet. Getting this in 9-9 would cut the WR time by ~30 minutes, so it is worth exploring, but it is extremely hard to even get an attempt going due to the nature of the stage. Video links will be made available shortly.
Use this glitch with extreme caution. It literally broke LudwigVonKoopa's computer mouse and keyboard. No joke.