Well done, an interesing ascii remake of minecraft. I felt like some basic collision detection could have added a bit more, like having areas blocked off by stone, where youd have to work up to mining through it, or getting stuck in a hole you dig. You could make it as simple as looking at the square next to you, and if its 'at the same level' then you could move there, if not, you cant move. I guess that takes it into another dimension as well though, youd have to handle displaying multiple levels of terrain but Im sure theres ways (like how dwarf fortress does for example)
The best thing to do in a game like this? Ascii art!
