Here's an improved Journey To Silius TAS. I managed to save 4603 frames (roughly 74 seconds) thanks to the wrong warps which were discovered by BadBrakes and Chambers_N has made some videos on them which helped me greatly.
Stage 1, Stage 2, Stage 5
These stages remain unchanged, I tried to improve them but it wasn't worth the hassle, those stages are solid already.
Stage 3 & Stage 4
Here's where all the time saves are. Around 5 years ago it was discovered that you could trick the game into thinking you went past a certain screen, thus triggering a checkpoint. By making the player walk very slowly at the end of an elevator you can make the current screen value (017E) increment if the X micro frame value (0031) is greater than zero, for each increment the X micro frame value will decrement. Using this trick and some damage boosts to get killed right after the manipulation I was able to save roughly 75 seconds.
Stage 5's First Boss
Due to the player placement right after the second wrong warp I had to use some extra ammo to beat the last enemy before stage 4's boss fight. Which meant that the game would automatically switch me back to the default weapon. So I had to lose 100 frames there.
Useful memory addresses
0506 - X Position (Cam) ; Unsigned 1 bit
0500 - X Position ; Unsigned 1 bit
0501 - X Position (Sub) ; Unsigned 1 bit
0507 - Y Position (Cam) ; Unsigned 1 bit
0504 - X-Speed ; Signed 1 bit
001F - Boss HP ; Unsigned 1 bit
00B0 - Player HP ; Unsigned 1 bit
00B1 - Player Ammo ; Unsigned 1 bit
Zakem66 for his TAS which this is based off, other than not having the wrong warps it is perfect.
BadBrakes for first reporting on this discovery.
Chambers_N for the videos he's made about this trick.
Very nice, great to see an improvement that uses the latest discoveries in this game.
I assume there is a reason the RTA-runs only death warp in stages 3 and 4. However, since there are continues in this game, it's not obvious how the number of lives would matter for this decision. It seems like the time it would take e.g. to fall into a pit at the beginning of stage 3 and force a game over could be weighed up by additional skips. Are there no suitable places for death warps in stages 1 and 2?
Finally, I'd like to add a few comments about this trick. I think it's correct that Chambers was the person who figured out the game mechanics behind the skips and worked on finding setups for doing them in RTA-runs. However, I believe 'badbrakes' was the first* person to report getting a death warp (https://forum.speeddemosarchive.com/post/journey_to_silius_21.html# ). I'm not familiar with the history between badbrakes' initial discovery and Chambers finding the explanation and setups, but I'm pretty sure it was a "known unknown" among speedrunners of the game, so Chambers knew what he was looking for. Not that this diminishes Chambers' work in any way, but thought it was still worth mentioning.
* To my understanding, the requirements for this trick are quite specific, but it's still a trick you can stumble upon by accident when playing normally (I think this is what badbrakes did). So it's not too unlikely to imagine that others have done it in the past too, just never reporting it publically.
Location: Western Europe
I did some testing and it seems like this trick only works when the screen scrolls to the left, which it never does in the first two stages.
Also thanks for clarifying who discovered the trick. I'll go change that in the notes.
I didn't expect this game to improve so much. I was deeply impressed and checked it in the emulator. I saved 2 lag in stage 1, but unable to synchronize in boss battle. I haven't done much research. I guess it is caused by the remnants of the enemy coordinate subpixels or bullet coordinate subpixels.
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Were you planning to look for further improvements or is this run safe to judge?
Warning: When making decisions, I try to collect as much data as possible before actually deciding. I try to abstract away and see the principles behind real world events and people's opinions. I try to generalize them and turn into something clear and reusable. I hate depending on unpredictable and having to make lottery guesses. Any problem can be solved by systems thinking and acting.
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