Slow Mole

General information

• Emulator used: FCEUX 2.6.0-interim git revision b4734ac45fe20cd0d8f65649b467b1c8ede8d068 (syncs on 2.6.2)
• 100% (normal game + bonus level)
• The single segment world record is 33m48s and does not complete the bonus level, while this TAS does and is 11m33s.
• Glitchless because I am aware of only one glitch, and it doesn't save much time.

Game basics and TAS notes

• This game requires very precise input and is definitely not meant to be easy for casual gamers. For instance, a two-frame window to jump over some obstacle is a regular occurence.
• There are specific frames on which you can jump on a spring before you bounce on it. Since we can control the mole's jump height, this often helps in synchronizing the mole with the game's cycles, which saves many frames on many occasions.
• Horizontal springs have something strange physics-wise going for them. If one propels you to the right, then it can be faster to hold left for a while even after contact with the spring.
• Vertical acceleration is to be handled in the same way as it is in games such as Mega Man: jump as high as possible before dropping from a platform so your vertical velocity is the greatest. This is particularly important in this game since this often allows us to save a cycle of whatever obstacle there is on a screen, and therefore save much more than just a few frames.
• Unlike other games such as Battle Kid, rooms do not always start in the same state: some enemies or obstacles have different starting positions. It is sometimes possible to manipulate those by leaving the previous screen later or in a different state (position or velocity wise), such that a more favorable screen allows for saving cycles.

Possible improvements

• I suspect there are some subpixel shenanigans I couldn't manage to understand, which makes the game very painful to TAS since seemingly minor input changes often desync the whole movie.
• The unused glitch (used in the current speedrun world record) allows the mole to pass through a floor in one specific room. It is possible it is usable in other places, which could make a glitched run worthwhile.
• I suspect slight movement optimizations exist due to the somewhat complex physics of some obstacles. I tried many different things in situations including these, so I am quite confident the savings due to such optimizations must be rather small.

Thanks

• Erik Rosenlund for the fun but very challenging game;
• Zorilla33 for his current world record run, which I find quite impressive;
• TASVideos, its staff and volunteers!