Interesting concept, but I have to admit that I thought the level design didn't always quite make the best of it (though I didn't play all the levels). Some of the levels made good use of the central mechanic, but for others, it just felt like it was slapped on without really influencing level design too much. I strongly advocate for undo buttons in puzzle games, but I appreciate that undo systems are not always trivial to implement, especially during a jam. Still, all in all, a pretty solid little puzzler.