I'd like to add an extra task for you, and it's up to you if you want to undertake it. Punch three guards in the butt (On MGS3, obviously, I don't think it's possible on the others). Just 'cause.

Anyway, you're on easy street as soon as you get a cobalt blue tarantula (or an emperor scorpion, but the spiders appear first).

...what about Snake's Revenge?