I don't know if any MGA!2 fans knew, but some of the rarest cards can be obtained by upgrading other cards. Here's some I've found, feel free to share.
LIQUID SNAKE > upgrade Master Miller card
REVOLVER OCELOT > upgrade Ocelot card
CYBORG NINJA > upgrade Grey Fox card
BIG BOSS > upgrade Naked Snake card
Know any more?
And..
EZ Gun- Do 6 levels on Arena mode at Easy Level
STEALTH- Do 6 levels on Arena mode at Normal Level
RUNNING MAN- Do 6 levels on Arena Mode at Hard Level
G36C- Do 6 levels on Arena Moade at Extreme Level
hey thanks for the help man :thumb: