Welcome, this is the discussion board of TASVideos.
If you have a question, please read the Site FAQ first to see if your question has already been answered.
Be sure your posts conform to Site Rules
We also have a Discord server and an IRC channel #tasvideos at irc.libera.chat...
Be sure your posts conform to Site Rules
We also have a Discord server and an IRC channel #tasvideos at irc.libera.chat...

Note the four divergent paths in the upper right quadrant.
Edit:
If there's not enough fuel for any of these. We'll instead need to start by jumping to the left, getting fuel and retracing our steps.





This should be the shortest route.
However, due to the enemy's I don't think the shortest route will be possible. They're really really annoying in this level.
A general idea for 21. Since there are no fuel pickups, I'll have to hang out in the charging square for whatever fuel is necessary, and if I end the level with any fuel left, then it's not optimized. I'll have to investigate the holes on the top half of the level - there's a depth at which it will be more worthwhile to dig through than to fly out and fall in. It might even be better to skip a lot of fuel and just dig through all of them...
All these alternates change fuel requirements, and time point differences will mean different enemy placement at other time points.
1) Grab the rightmost gem before heading to the left, if the Marble and Missile are out of the way, no enemy's to bother you, and a more direct finish to the level.
2) Perhaps bust a wall on your way up? You can bust the brick directly to the right of the gem, or the one above it, on your way there, and then go through it on the way back, which direction you need to go in anyway.
3) Go above, maybe you can more effectively go around the springs this way. For one thing, it looks like a cleaner way to get to the door on return.



Don't know if it works or not.
Edit: Exchanging where the path first crosses is better, if possible.
Edit 2: Or maybe switching the initial start direction with the part of the path that goes through start later, by going down and right instead.
This plus better horizontal movement should shave some more time off this...