That question is very vague. If the wp you mention is indeed wordpress, by saying you want to hack it I will assume you want to modify wordpress to make an online game. If that is the case, you need to learn a lot, and I mean a big big lot of web design. How ever to make a game you would be better of studying very must in a lot of different areas such as algorithms, mathematics and disregard the idea of modifying a blog tool.
