This is an amazing little game! Even if it's only a demo, I actually found it enjoyable as a game on its own.
I really liked the originality of the "merging" mechanic and how it can form challenging puzzles with just a few simple rules. I also enjoyed how the game is controlled smoothly.
The only minor issues I had were about dropping symbols: pressing Down every time felt less smooth. Especially in the later levels, with the gravity-reversing power, it felt less intuitive to me to understand how to use it to solve some puzzles.
All in all, I thought it was an refreshingly original puzzle game, and even more impressive considering it was coded for a retro console. I am looking forward to the final version!
Really great game that ran great on my Powkiddy v90! I hope you're able to come back and add the rest of the levels!