This is a very hard single level (3-1, there is also 3-2, but it's just the ending). It requires perfect knowledge of the game and great skill. It features almost all items of the game and makes sure you use them correctly. This is mostly about a lot of challenging puzzles (there are some hints) and hard moves (but not insanely unfeasible). Just in case you wonder, there IS a solution (there might even be one I didn't think of), trust me ;)
Your goal is to enter the "Impenetrable Tower". Tough mysteries and enemies will prevent you from doing so. Will you be the hero able to reach the entrance of the tower?