Alex Mercer-GIVE ME SOMMA THAT THERE VIRUS!!!!
The Lich King- What better wingman at a bar than an 8 foot tall undead guy with a sword that eats people's souls?
Necron Lord- Silent, but when you absolutely, positively have to crash your office's network, terrify your co-workers, and generally turn a boring day at the office into an exciting one, accept no substitutes.
Frank west-He's covered wars you know.
Samus- no explanation needed
Big Boss- Simply being his friend makes your badass score rise 9000 points. or over 9000.
all I can think of