I don't think it is possible for me to name one specific best moment with a Bungie game, but rather the experience as a whole. For a good 2 years or so, Halo 3 was literally my life. The first and last thing I did in a day was play Halo 3 (well, first thing I did when I got home). On weekends EVERY SINGLE NIGHT I stayed up to play that game until no sooner than 3 at night. The custom games in it were amazing and I loved all of them. Were it not for Halo 3, I would have never gotten the internet, a gold subscription, or multiple Xbox's because they drop like flies. It also brought me to this website every single day of my life (though on my Riley1997 account) just to do stuff in the forums and to download maps. This was my ultimate Bungie moment, not one specific period of time but the entire experience as a whole.