Successfully complete the indicated task to get the corresponding ranking to appear next to your name online:

Bear: Perform a lot of CQC attacks.
Bee: Perform a lot of scans.
Chimera: Have a lot of sniper kills.
Crocodile: Have a very good kill/death ratio.
Dove: Perform a lot of non-lethal attacks.
Eagle: Have a large percentage of headshots.
Flying Squirrel: Have a high percentage of rolling.
GA-KO: Prefer Rescue rules.
Jaws: Perform a lot of knife kills.
Kerotan: Perform a lot of captures.
Night Owl: Use the ENVG a lot.
Pigeon: Perform a lot of non-lethal attacks.
Rat: Fall for a lot of traps.
Road Runner: Run a majority of the time.
Sloth: Get shot in the head a lot.
Snake: Play a lot of sneaking missions.
Turtle: Use the cardboard box a lot.

Progress through Metal Gear Solid 4: Guns Of The Patriots to unlock new songs in Metal Gear Online. All songs will become unlocked with a cleared saved game file from Metal Gear Solid 4: Guns Of The Patriots. Note: Continuing a new game session on a cleared saved game file will cause all Metal Gear Online tracks to become locked again until you pass the point where they are normally unlocked.

While playing the game, type <song> in the chat window to have your character sing a part of the Metal Gear Online melody.

At the character selections screen, remain idle. Your character will hide in a box or start reading a magazine.

When playing in stages where your breath frosts, have Snake play dead while prone, and his frosty breath will no longer be seen by others.

At the selection screen, keep spinning your character in circles. When you stop, he will get dizzy and fall over.