Halo 2 was a game that changed online play with better multiplayer, and it gave you the ability to play with friends like never before. My own experience was always one of awe and wonder, no matter how many times I played through the game. Even though the servers have been shut down, if you never experienced Halo 2 yet, you need to play it. Soon.
Halo 4 brings new life to a series that was meant to be over. Many gamers, and even lovers of the series, felt awkward about bringing a new game to the series, but almost all agree that this is a fantastic new direction to take it.