Let's summarize the first day.

In the few hours I managed to allocate for development, I was able to: - Set up the platformer base using a wonderful example from Defold. - Spent a while figuring out how to connect an orthogonal camera to be able to track mouse coordinates. It will be needed a bit later. - Started sketching the visuals. I spent some time with the character. Surprisingly, Inkscape was more helpful for conceptualizing and determining the overall shape. But for the actual game, I decided to quickly create pixelart for the bug in Aseprite, with animations.
The concept:

What's next? - I'll try to implement the mechanic from the initial idea after all. Maybe this bug will be able to crawl on walls, we'll see. - I'll spend the remaining time on creating the atmosphere so that the visuals don't feel too raw.