1. when I first realized I could easily kill my bro by running him over with the Warthog
2. when I first realized I could send a huge blast (that took down shields) if I just waited a sec to let my gun 'charge up'
3. when I first heard the little aliens say "run for your lives" and curse (hilarious)
4. when I first saw & played the game through a demo that started on the Silent Cartographer stage where you drive the Warthog. That demo made me and my bro go half on the game the same day