Submission #6531: the0nlykyd's Genesis Sonic 3D Blast in 24:09.80

Sonic 3D Blast is an isometric platformer for the Sega Genesis made by Traveler's Tales.

This is a fairly straight-forward run. The game is pretty well put together and doesn't include much in the way of exploits, clips, glitches, etc. There are 2 instances of intentionally taking damage. There are no deaths. No use of Level Select. Flickies can be grabbed by Sonic or by other Flickies already following Sonic. The objective of this TAS is to reach the End Credits as fast as possible without using Stage Select.

This TAS is, in large part, carried over from the Best Ending TAS. Many of the existing segments from that TAS were preserved here, with the bulk of the changes being in stages that included Special Stage entries. Seeing as this is a more often-run category I felt it necessary to has a TAS of it for posterity. I also included a bit more of the technical information regarding movement in this submission as opposed to just the very simplified breakdown from the previous submission.

Movement

Movement optimization was key. I ended up doing a lot of experiments in addition to referencing other work done in the game. Specifics will be explained in detail below but the short version is as follows:

Running

The default means of movement. Sonic accelerates from standstill to full speed in just over half a second. Sonic's turns, while very slidey, are best when running versus his other movement options (exception being wall bounces when rolling, explained below). Sonic presents no hitbox to damage enemies or obstacles when running, making this his most vulnerable movement option. It's best to run only to accelerate to top speed or to turn corners.

Slopes have various effects on running, but typically the only noticeable effects are running up steep slopes. Running up shallow slopes has no noticeable effect. Running down shallow slopes seems to likewise present no obvious benefit. Steeper slopes range from not very beneficial to outright horrendous. Running down a steep slope often sees Sonic just drift off of them with his momentum and become briefly airborne. Running up steep slopes rapidly decelerates Sonic to the point where he can actually be forced to a full stop and taken downward. I don't have any numerical specifics for slope interactions with running, but you'll typically avoid running on slopes anyway due to superior movement options.

Rolling and Spindash

Roll and Spindash share a single designated button in this game. If Sonic is moving laterally when the button is pressed, he'll curl into a ball and maintain the speed for roughly 10 frames before rapidly decelerating.

If Sonic is at a stand still, he'll instead curl up and start revving up a spindash. Spindash has 4 stages (what I'll be referring to as 0-3). The first charge (0) is achieved 11 frames into holding the button. A timer then starts counting down from 15 to 0 every frame, upon reaching 0 it will reset and increase Sonic's Spindash Charge by 1. Charging a spindash from standstill to full this way takes 56 frames, just under a full second. The process can be assisted by pressing a Jump button between revs to increase the charge by 1 and reset the rev counter before the normal 15 frame timer finishes. It's best to try to time this right after the first charge is reached (when you hear the audio cue) then again as soon as you hear the next charge. This should cut down the time to full charge significantly. For TAS, the full charge can be reached in 16 frames, with frame 17 being the launch. Sonic's highest 2 charges both have a higher speed cap than running and jumping normally, with the highest charge being faster than Sonic's speedshoes speed caps. Like rolling, Sonic will start to rapidly decelerate after a short time.

Sonic obviously also has a hitbox for this making it possible to destroy enemies and certain obstacles in this form. Sonic's turning is pretty horrible and he'll uncurl completely if the turn is too sharp of an angle. Rolling into a wall bounces Sonic off that wall with his speed preserved. Rolling into the wall diagonally results in Sonic being bounced off in a 90 degree angle while rolling directly into a wall bounces Sonic back in the opposite direction. Interestingly, the game can tell the difference between Sonic being in a Rolling state and Jumping state, even when airborne. Rolling off a ramp into a wall will still result in Sonic bouncing off the wall while in the air.

Rolling and Spindash inputs can be stored when Sonic is descending, which can help maintain momentum or begin a spindash sooner and under a couple of circumstances where they might not normally be possible (an easy example is storing spindash on the first checkpoint ring break in Spring Stadium 2). Lastly, it's worth noting that supersneakers have no effect at all on Sonic's spindash speeds.

Spindash Launch Speeds:

Slopes definitely seem to have a more noticeable effect on rolling speed than running speed. The deceleration for inclines and acceleration for declines is more immediate. That said, you're still not likely to see these interactions often since better options are available.

Jumping

Sonic's only means of vertical movement by default (terrain specific options such as springs exist). Sonic accelerates slower when using jumps, but maintains a VERY SLIGHTLY higher top speed than when running. Steering is possible when airborne, but the arcs will be wider than taking turns while running. Jump inputs can be stored when descending. This allows you to press (and hold) jump as you descend to store another jump, which keeps Sonic curled up to never drop his hitbox.

When Sonic has the Gold Shield upgrade, the Jump Input storage is replaced with specific powers. When an enemy is nearby, Sonic can press Jump again in the air to Homing Attack that enemy, with him bouncing directly up with no momentum on impact. If no enemy is within range, Sonic instead will Stomp directly down killing all his momentum. This Stomp has very good synergy with Spindashes due to its ability to stop Sonic's momentum to prevent rolling, which can effectively start a spindash from a run in 19 frames. When this can be done often, it generally outpaces the boost of speedshoes.

Moving with constant use of this jump storage presents the benefit of having a hitbox up to destroy enemies and avoid specific obstacles (Spring Stadium spikes, Gene Gadget shock panels, etc) while keeping a similar max speed to running. Even though he turns aren't as tight, they're not exactly bad. I honestly recommend using this as your primary means of movement under general circumstances.

1: Assuming jump on first frame of movement then continuing with jump storage until full speed is reached.

Slope interactions with jumping is going to be significant in optimal movement. You never want to jump on an incline and ALWAYS want to jump on a decline. For an incline, it's best to jump at the base before the slope to try and make your way as far up as you can then running the rest of the way. Jumpin on an incline causes Sonic to take a sharp cut in speed since the slope will always try to launch Sonic in the direction perpendicular to it. For declines, it's best to jump as soon as you can for a brief burst of extra speed.

If you're going fast enough, you can actually reach this game's true speed cap with a downward slope jump. When this cap is reached it is maintained for as long as Sonic is moving that same direction or until he is obstructed by a steep slope, wall, enemy, or other obstacle. I'm not sure why this speed cap is maintained like this but I suspect it might be due to the coding of Diamond Dust's slides, which behave similarly. The numerical data below is the expected speed boost from downward slope jumps under various circumstances.

Specific Changes from Best Ending TAS

All stages not listed here are directly imported from the final revision of the Best Ending TAS.

Green Grove 2

Green Grove 3

Spring Stadium 1

Spring Stadium 2

Spring Stadium 3

Diamond Dust 1

Diamond Dust 2

Volcano Valley 2

IL Times

Special Thanks

While I didn't have much in the way of consultation with this TAS, contributions I got from SegaJunkie, Zurggriff, AmberCyprian, CoEmpathy, and Kuryami all played a strong role in the previous TAS that served as a basis for this one.

Masterjun: Judging.

Masterjun: Looks very nice. Feedback seems to be good as well. Accepting to Moons as a new entry for this game.

fsvgm777: Processing.