VBGamer

Disclarimer: I am not a lawyer.  Software is tricky.  Technically the written work, (the source code), is original work even though it accomplished the same thing, so he couldn't be sued for that.  I don't know if the artwork is the same, I never played the original game.  In terms of artwork and music, if those are similar then you could be sued for that. I don't know if anyone has a patent on the game play, but that's something to consider.  Apple and Microsoft have patents on their GUI and the functionality of their GUI, and someone could probably start patenting those concepts in games.  Of course, patents, copyrights, and trade marks are all different concepts in terms of the law, but you can still be sued for infringing on any of them.

The only protection that I know of is to create a parody of the game.  However, I don't think this work as it is could be classified as a parody.  If you were to change the graphics to something else, such as pictures of the U.S. President, then you could probably argue that version of the game as a parody.  Their could still be one remaining problem.  A company could still file a lawsuit against you to bring you to court even though they may not win, it will cost you lots of money for legal fees.  This tactic is used to bankrupt people into doing what the larger company wants them to do.

Of course, there really is no money in this sort of game. I can't imagine Lolo 2 outselling Halo 2.