Snake escapes Gene's clutches with the help of a wounded Green Beret named Roy Campbell, but two men aren't enough to stop the army of American and Soviet turncoats Gene controls. So instead of focusing on things like complicated puzzles, traps or gadgets, Portable Ops tasks you with building and managing your own army, one soldier at a time.
So forget about the simple joys of snapping necks. To recruit an army, you'll need to use a little restraint - along with Snake's tranquilizer pistol, his patented Close-Quarters Combat skills and Roy's waiting truck - and kidnap your enemies instead of killing them. The good news is that you can recruit hundreds of troops this way, and everyone you see - from grunts and officers to politicians and doctors - is fair game. Even the game's formidable bosses will join you, provided you defeat them non-lethally, and you'll even get an alternate cutscene for your trouble.
You'll need their diverse talents, too, as your troops will be used to assemble four "sneaking" squads (which you'll actually take into missions), as well as a medical team and a tech team to produce medicines and new gadgets. You'll also be able to send your converts into mission areas as spies, at which point they'll steal ammo, feed you information or otherwise sabotage the enemy.