[aaronetz]

Thanks for the feedback! If the hard level is pretty hard, wouldn't adding more operations make it even harder? I kept the number range small because I felt it would be too hard to do mentally otherwise, but I'm definitely open to extending it. The idea was novel for me but I was quite certain it has been done before in one way or another.

[pbhjpbhj]

It would probably make the hard level even harder (assuming unique solutions then definitely) but for the lower levels it would provide a wide range of play styles and so more replayability - I'd probably be more inclined to play intermediate with wider ranges and/or other operations than to play hard in "simple" mode.