I played the demo after seeing Aliensrock play this game, and I really enjoyed it. However, it was a tad bit annoying how some levels pretty much required me to pull out a piece of paper and write down the combined key and door values and figure out how to solve the puzzle through math. That's why I'm so glad that there was an in-game note system created. It's really great to be able to put all my notes on the screen so I don't have to look away every few seconds.