Dog Tags are collectible items in Metal Gear Solid 2. To collect them, simply hold up a guard, get in front of them and look at them in first person view. If there is a twinkle on their chest, then they have a dog tag you can obtain. You can make them give up the dog tag by aiming at their head or groin. They will then shake their dog tags (and, eventually, other items) for you to pick up. The player can also use thermal goggles to look at a guard from the front to tell if that guard is carrying dog tags.
Some of the guards will refuse to give you anything at first. If this is the case, then shooting the guard in a non-lethal area (ideally the arm or leg) or aiming a more potent weapon (such as the Nikita) will usually persuade them to give it up.
You can view dog tags by going into the special menu, selecting Dog Tag Viewer, and choosing a save file to load dog tags from.
Rewards for collected dog tags include:
Snake (Tanker):
Infinite ammo bandanna - 46 dog tags
Stealth Camouflage - 76 dog tags
Raiden (Plant):
Brown Wig (infinite ammo) - 73 dog tags
Stealth Camouflage - 120 dog tags
Orange Wig (infinite hanging meter) - 170 dog tags
Blue Wig (infinite O2 gauge underwater) - 218 dog tags
The names on the dog tags are taken from Konami contest winners and the games designers, and one dog tag in the Tanker Episode is named for J-Rock singer Gackt, who also did a Japanese television commercial for MGS2.
Also, some characters have their tag on them, or the tag of another character in the game. Olga Gurlukovich carries her own dog tag, Fatman carries Peter Stillman's dog tag, and Solid Snake carries a different dog tag on each difficulty level: Iriquois Pliskin on Very Easy, Meryl Silverburgh on Easy, Solid Snake on Normal, Liquid Snake on Hard, and Hideo Kojima on Extreme or European Extreme. Each of these special dog tags can be obtained by shaking down the character's body after knocking them out (or, in Fatman's case, killing him). Snake can only be knocked out in Arsenal Gear, immediately after being reunited with Raiden; at the time, Raiden can only use punches, kicks, the summersault attack, and the HF Blade, which needs to be set to non-lethal by pressing the Weapon Button.
