^ Kirua could not have said it much better
what happened was the thing where you can double jump after grabbing a mushroom or fireflower as seen in this video by andrewg Look around the 1:05 mark.
it is actually pirhanna plants, due to poor programming they are now invisible, but still have hitboxes. just avoid the tops of pipes lol
There are actually 32 levels in Super Mr. Krabs, but only 30 are accessible. In this category, you play through those 30 levels. 1-1 1-2 -1 -2 -3 -4 2-1 2-2 2-3 2-4 3-1 3-2 3-3 3-4 4-1 4-2 4-3 4-4 5-1 5-2 5-3 5-4 6-1 6-2 6-3 6-4 7-1 7-2 7-3 7-4
Timing starts when you take control of Krabs in 1-1, and ends when you touch the axe in 7-4. No resets are allowed.
To give an example I did a run, which is very bad. Here it is. I don't even know what I was doing in 5-2 DansGame.