Complete the indicated task to unlock the corresponding weapon.

Weapon	How to unlock
Bandanna	Complete a single-player session without killing anyone (including bosses). You can do this on any difficulty
Desert Eagle, Long Barrel	Earn the Fox emblem on a single-player session
Digital Camera	In the Nomad vehicle during the mission intermission; you can unlock a special photo by picking up this item in stage 4 instead of earlier
Patriot Future Assault Weapon	Earn the Big Boss emblem on a single-player session
Race (Ricochet) Gun	Clear the single-player game once
Scanning Plug S	Log more than 10 hours of Metal Gear Online play time on the same profile as your Metal Gear 4 game. You purchase this from Drebin
Solar Gun	Collect the five statues (those of the four Battle Beauties and the Frog Soldier/Haven Troopers in stage 1) using non-lethal means on their respective idols
Stealth Item	Complete a single-player session without instigating a single alert (caution is okay, but not alert). You can do this on any difficulty
Thor 45-70	Earn the Fox Hound emblem on a single-player session
World War I Pistol	Earn the Hound emblem on a single-player session