Most difficult levels in existence?

[geodave]

Dave, it's also one of your most memorable and one of my favorites! I solved it blind and then optimized it using a map, and enjoyed it very much. It's a concept that really can't work without invalid tiles, the maze has several solutions, and not every lock is guesswork (though many are, but they aren't surprising cooks, since you know you have to guess correctly or it's cooked).

-Miika

Well thanks! No one has ever told me they liked Key Hell.

I think that there may eventually be another set with invalid tiles, but it will be a while in coming. A lot of the things you CAN do you really SHOULDN'T do. I had originally planned on having some in geodave4.ccl, however most of my concepts were just silly or easily converted to Lynx-compatibility.