Thanks a lot! Yeah, the fact that the game has "letting time pass" as a mechanic has its ups and downs, I think it only works in a short game or it would get very tiresome. I did have the idea of making the speed and direction of the frames to be controlled by the player, and had it almost implemented, but were a tad too many inputs and didn't manage to milk it very much at all.
The implementation of the frames is super super dirty. On one side, the images you see are unrelated to the colliders, and just draw one frame from the left side of the screen until the position of the "sweeper", and then the next frame from the sweeper to the end.
The colliders are made up of vertically thin blocks that whenever their x position is equal to the sweeper position they check if the frame the game is in is the frame they are in. If true, they teleport onto the level, else they just teleport to y = -1000 or something like that.
Thanks for playing and supporting me! :D