Sometimes when you start sketching you have no idea where it’s going to end up.
The sudden appearance of the ground and addition details is the result of the ProCreate app continually crashing while editing the layer. Apparently the “record” function just ignored what I was doing and jumps ahead of the glitch. To the app developers credit, the app doesn’t lose the picture itself when these crashes happen, and even though ProCreate doesn’t bill itself as an animation tool, the crashing and subsequent hiccups in the playback sequence drive me nuts. The rest of the app is so polished that it really highlights the problems when they occur.