From Emanuele Feronato: "One month ago I showed you how the HTML5 game engine to create GameBoy blockbuster “Pyramids of Ra” with the first playable level, but the game gets much harder as you progress through the levels, adding new types of tiles.
The first new tile you will find is a harder tile which needs the player to cross it twice before disappearing.
I placed it on level two of the game, so I am sorry but you have to solve level one before seeing the new tile."