I've told calebsoong (eNetro50) more than once that I'll do a Gravity = 8; video, but I never got around to doing so until now. In the back of my mind, I've also wanted to do one of these for quite a while. I've chosen levels that don't give very obvious paths or take longer than the normal gravity runs. Many levels have multiple paths, and some paths take advantage of movements that are not possible in normal gravity but are possible in lower gravity. The reason why I chose 8 as the gravity value, back in 2009, is that it is the closest integer to the geometric mean of 20 (the normal gravity) and 3 (the Gyrocopter gravity).
To modify the gravity in a level: Add the line defaultmarble.gravity=8; (without the quotes) between the second-to-last line and the last line of the .mis file.
Notes:
Learning to Roll: Just showing what the gravity does.
Pitfalls: It is surprisingly possible to edge-hit (almost!) up to the finish platform.
Platform Party: Another run just showing the gravity. I originally had this right after LtR but some Pitfalls came between them.
Great Divide: You can get to the Time Travel earlier. It should be possible to get that TT on the middle tower before the finish, but I didn't feel like trying.
Great Divide Revisited: I had a low 9.xx on the Time Travels until I carefully worked out the landing and jumping beforehand to get below 9 seconds. Best catch 8.28 but the time restarted. I don't need to get the last Time Travel on the second pink platform, which is good since I need to turn the marble to get it, and that decreases its speed and then I can't seem to get it up to the finish platform.
Survival of the Fittest: This was the fastest path I could find. When I tried to get the last Time Travel directly, I would have too much leftwards movement to properly rebound to the right afterwards.
Whirl: An old path I found in 2009 but with the start I use now (different from the start I used then). I think I got 3.73 or so back then (it's close to or equal to my best catch now) but I'm not sure how I could have done it.
Path of Least Resistance: Arch hit….
Ordeal: Two paths for 6.xx, one of them doesn't even use the Super Speed.
Battlements: Another 2009 path, I really like this path.
Gravity Knot: The two paths here are two different simplifications of JRONI's unsuccessful normal gravity Big Marble path.
Keep on Rollin': In normal gravity, there seems to be no way to use the Super Jump without, you know, dropping down from the finish platform or something. In lower gravity, on the other hand, ….
Floor Climb: Inspired by my No Jumping run. One of my interests in this game is how paths from modification runs (no gems, low gravity, no jumping, etc.) can help with runs on standard settings as well as runs using a different type of modification.
Fighting Slopes: If you try an edge hit at the start using normal gravity, you probably won't quite make it up the slope. In low gravity, it became almost too easy and I found that the sign hit approach might be faster. It's possible to go from the last diamond straight to the finish by wall-hitting on the wall below the finish pad, but the trim got in the way at least 90% of the time.
Songs: Muse - Undisclosed Desires, Will Bedford music - Prometheus (a Portal 2 song/remix).
A time can be beaten, but a path can't be rediscovered. The best path stays forever.