This game is great! I started a TAS right after i saw the speedrun, which uses a few good techniques. Here's my lua script, for BizHawk. I guess my run is halfway done, right after taking the iron ball. My route is the same of the speedrun.
You're a bubble. Later you're still a bubble, but with powerups.
A small Metroidvania by morphcat for NESdev compo 2019. More info and download here here.
Link to video
Any% Speedrun in 3:25 by Skunky48. There's also 100% speedruns which collect all ducks in the world. The speedrun utilizes some OOB glitches to get the Double Jump faster.
I would like to see a TAS of the game, although I don't know if the developers are going to continue on the project. I certainly think it'd be entertaining.
Opinions?
This only works in the U version of the game, and it only works on right walls.
You may zip either upward, if you're low on the screen, or downward if you're up high on the screen. If you're in the wrong position, you may end up below the screen and die.
In vertical rooms, this trick can be used to perform huge leaps, which can allow you to clear them quickly. If you do it more than once in a room, you can break the screen scrolling, which can potentially be used for more stair dismounts also.
Here's a short demonstration of where it can be useful in a TAS:
Link to video
This trick opens up a huge amount of new possibilities for a new Grant TAS. It might be faster to use the U version now, even for a non-wrong warp TAS. There's also a possibility now that the lower swamp route is faster now, since many of the rooms in that route might now be skippable.
Due to imperfect manufacturing technologies of the time and poor separation between the analog and digital parts of the chip, the 6581's output (before the amplifier stage) was always slightly biased from the zero level. Each time the volume register was altered, an audible click was produced. By quickly adjusting the amplifier's gain through the main 4-bit volume register, this bias could be modulated as PCM, resulting in a "virtual" fourth channel allowing 4-bit digital sample playback.
Eh, I think they should have waited until melonds was integrated before releasing.