@desiree I Wanna Lockpick: one thing I like is that most of the level designs are "evil", in that they have an setup that would work, except you're one key short, and you have to find the weird alternative that does work.
imaginary keys and imaginary doors really annoy me for some reason. I almost stopped there, but I kept going a bit, and now I'm in middle of the next big complication, and not sure if I want to expend the energy to map out all the steps needed to open the next door