Submission #1198: nitsuja's Genesis Sonic The Hedgehog 2 in 19:55.43

Sega Genesis
(Submitted: Sonic The Hedgehog 2)
baseline
Gens 9h
71726
60
56605
Unknown
Sonic The Hedgehog 2 (W) [!].bin
Submitted by nitsuja on 9/13/2006 11:13:26 PM
Submission Comments
I think everyone's already familiar with Sonic 2, or if they aren't, they should be. I hadn't intended to work on this since Quietust was working on a redo, but I suppose you can blame AngerFist for this submission. It didn't take as much effort as some of the other runs I've done thanks to the existing run (and what little was said about the redo). Going by in-level time units, this turned out to be exactly 2 minutes faster than Quietust's v1. I used Sonic + Tails and (unlike the first run) controlled both of them directly, although a good deal of the the improvement did not involve using 2 characters. The largest improvements came from using new shortcuts and glitches, a couple of them to which I can't claim credit (Chemical Plant 2 and Hill Top 1), with a lesser amount of improvement from playing with more precision.
LevelTimeUnits Improved
Emerald Hill 10:171
Emerald Hill 20:351
Chemical Plant 10:170
Chemical Plant 20:3318
Aquatic Ruin 10:172
Aquatic Ruin 20:362
Casino Night 10:241
Casino Night 20:496
Hill Top 10:2811
Hill Top 20:444
Mystic Cave 10:253
Mystic Cave 20:352
Oil Ocean 10:233
Oil Ocean 20:3117
Metropolis 10:4410
Metropolis 20:437
Metropolis 31:0822
Sky Chase2:060
Wing Fortress1:348
Death Egg0:402
Total13:49120 seconds
Sky Chase is a fixed-length autoscroller, so I got 100% of the rings and killed 100% of the enemies to try to keep it entertaining. Everything else is faster than the previous run, although for Chemical Plant 1 it isn't by enough frames to save any full time units on that level.
Tails is really smaller than Sonic, thus he interacts with the levels differently and I couldn't simply copy all of Sonic's controls to make Tails keep up. Sometimes that means it is impossible for Tails to keep up, as he can't get going as fast on some types of curves. And Tails can't get items, so can't possibly keep up with Sonic when he has Sprint Shoes. But sometimes Tails lags behind simply because he wouldn't be useful and it's more of a stylistic choice to have Sonic always be the faster one.
I confirmed that lag frames do not count toward the in-level timer, so I did nothing to avoid them, as my goal was to minimize in-level time (even the part of it that isn't displayed). Almost anything different to avoid the lag would have been much slower, anyway.
General movie making: Some of the places where I controlled Sonic and Tails at the same time were just getting too tedious to record (especially Mystic Cave 1), so I modified Gens to let me record the Sonic and Tails parts individually, and merge them. Also, as I've gotten used to having a Sonic speedometer available in other runs (for other emulators), I added that too.
Chemical Plant 2: The door for the huge shortcut opens because Tails is lagging behind just enough for him to open the door exactly as Sonic is about to hit it.
Casino Night 1: I was nearly able to improve the end by at least another full time unit by jumping over the last flipper, but it wasn't possible to get going quite fast enough to make it across that gap.
Casino Night 2: Some collision-related glitches here saved a decent amount of time (going through flippers and skipping a stopper).
Hill Top 1: Getting Sonic to zip that far was really hard, I don't know how Quietust found it so quickly. After hundreds of failures I wrote a simple random input generator and it happened to find something that worked, eventually.
Hill Top 2: Those platform jumps are difficult and would not have worked if I had lost any frames anywhere else earlier in the level.
Oil Ocean 1&2: I was pleasantly surprised at how nicely these worked out. Oil is better than solid ground in some ways...
Wing Fortress: I duck at the optimal time at the end to make the barrier sprite disappear so I can dash through it before the camera goes back, ending the level without waiting for it to fade away. Those sliders let you perform or store spindashes while on them. I found a related bug that lets Sonic hover across almost anything in the level (including over or under or into the boss fight), but it disables spindashes and only works at a location most of the way into the level, and so couldn't save any time.
Metropolis 1: Sometimes it's faster to let Tails fly to catch up with Sonic than it is to slow down Sonic enough to keep Tails onscreen, especially after double-jump slope speedups which Tails is too small to do.
Metropolis 2: The trick at the start is the same concept as the Hill Top 1 trick. It saved about 2 seconds.
Metropolis 3: Finally, a conveniently-located crusher. I exploit the way that Sonic can't usually be crushed right after he starts jumping. Normally, doing this trick drops you into the spinning tube/cage, which is slow but still worth the large shortcut, but I found a way to zip past that before falling.
Death Egg: The back-and-forth dash between the doors before Eggman actually saves time. The third hit against Eggman is almost impossible to replicate. The running through the tunnel after the movie ends is faster than normal because of hitting the ceiling in a spindash jump at the last moment that Sonic has control.
  • No death
  • Aims for fastest (primarily in-level) time
  • Ignores delays caused by bonus effects
  • Takes damage to save time
  • Abuses programming errors in the game
  • One player controls two characters
  • Emulator used: Gens Movie Test 9h (works with 9f, etc.)

Truncated: Well, no sense in waiting here, this is accepted for being a first-class movie.
Last Edited by on 1/1/2022 6:13 PM
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