World War I Pistol - Earn the Hound emblem on a single-player session by doing the following: instigate no more than 3 alerts (the third alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Naked Normal difficulty (or higher) under 6 hours and 30 minutes.

Desert Eagle, Long Barrel - Earn the Fox emblem on a single-player session by doing the following: instigate no more than 5 alerts (the fifth alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Naked Normal difficulty (or higher) under 6 hours.

Thor 45-70 - Earn the Fox Hound emblem on a single-player session by doing the following: instigate no more than 3 alerts (the third alert means failure); kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Big Boss Hard difficulty (or higher) under 5 hours and 30 minutes.

Patriot Future Assault Weapon - Earn the Big Boss emblem on a single-player session by doing the following: instigate no alerts; kill no enemies (not even bosses); do not continue (at all); do not use life recovery items (at all); do not use the stealth suit or bandanna special items (you may possess, but not activate them); and complete the game on Big Boss Extreme difficulty under 5 hours.

Race (Ricochet) Gun - Clear the single-player game once.

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.

• Frog Statue - Stage 1 Middle East, Advent Palace garage, atop the Nomad vehicle.
• Octopus Statue - Stage 2 South America, Research Lab boss room, upper right room.
• Raven Statue - Stage 3 Europe, top floor of the human phase of the boss fight.
• Wolf Statue - Stage 4 Shadow Moses, behind Snake's starting spot in the human phase of the boss fight.
• Mantis Statue - Stage 5 Outer Heaven, near the northern most door during the human phase of the fight.

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.

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.

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.

Bandanna - Complete a single-player session without killing anyone (including bosses). You can do this on any difficulty.