Don't worry about crossing the streams with the Sega Genesis "Ghostbusters" game. Take on the first four levels in any order you choose to unlock the fifth and sixth levels and win the game. The open-ended game design lets you play the game in the order you want, but you still need to clear each level to advance to the last two. In addition to the end boss, each stage also has between one and four middle bosses that also have to be cleared to pass the level. Between levels, you can visit various stores to buy everything from weapon upgrades to proton packs. Start playing and show you aren't afraid of no ghost.