I decided to do things the easiest way, code wise. To unlock the exit to a level, you need to open all the boxes within that level. Nice and simple.
There are 10 level layouts currently in the game. I might add more, I'm not sure. So far the largest level only uses up about 1/16th of the available map size, but if I make them too big they get a little dull.
So, 10 levels, and then it loops back with a higher difficulty, going right up to level 100.
There's plenty of pickups, 3 types of enemies, and even a stash of TNT to blow 'em all up with.
I've also played about with the colourings a little. There are 6 Background colour schemes, and the engine picks out one colour for floors, one for buttons and one for blocks. It keeps things a little more interesting instead of it all being drab sandy yellow throughout.

The game, as it stands, is pretty much what I'd aimed for when I started. It has all the elements I'd planned and a fair few more.
But I've two more weeks before the Monthly Challenge's deadline.
What more could I add?
I'm sure I'll think of something!

Greenie - The Eccentric Egyptologist - Coming soon!

|update| The final release is available here |update|