44. Everyone Pees Themselves (Otacon, Emma Emmerich, Sokolov)
Another running joke in the series, three different characters in three different games pee themselves in front of Snake. You'd think that he'd just start carrying diapers in his prodigious utility belt so he could clean them up and get moving.
43. Johnny Craps Himself In Every Game
Despite the Metal Gear games being mostly about the travesties of war, there's a pretty consistent serving of bathroom humor in each game. Johnny is a character with a perennially upset stomach, and even MGS3, which takes place in 1964, has a Johnny with gastrointestinal issues. This is revealed to be the grandfather of the Johnny in the games set in the 21st century.
42. Snake Never Laughs
Aside from an occasional derisive chuckle, Snake is a man without a sense of humor. Even when his associates crack jokes over his Codec, the punchlines are met with a quiet grumble, or something along the lines of "I don't get it". You'd think he'd jump at any opportunity to break up the tension of, you know, averting the simultaneous mutually assured destruction of all the world's superpowers.