Completion bonus - Successfully complete Campaign mode to unlock the character, environmental, and weapon concept art at the "Extras" menu.

Accomplish the indicated achievement to get the corresponding number of Gamerscore points:

Clingy (25 points): Kill 15 enemies in a row by grappling them on any difficulty.
Combat Veteran (25 points): Kill 250 enemies in the campaign on any difficulty.
Compat Experience (10 points): Kill 50 enemies in the campaign on any difficulty.
Dead-eye (50 points): Complete any mission with an accuracy of 80% or higher on Normal or higher difficulty.
Defender (20 points): Help defend the barricade in New York on Normal or higher difficulty.
Dolly Madison Award (20 points): Save the Constitution from being burned on Normal or higher Difficulty.
Environmentalism (15 points): Complete 40 environmental or grapple kills on any difficulty.
Exploding Monkey (20 points): Kill at least Four enemies with one explosion on any difficulty.
Going Nuclear (30 points): Rewire an Atom Bomb on Normal or Higher difficulty.
Gravity is a Harsh Mistress (5 points): Toss a paratrooper onto the streets below New York on any Difficulty.
I Saved the General (20 points): Rescue General Donnelly from the D.C. courthouse on Normal or higher difficulty.
Impeached (30 points): Oust the false President from office on any difficulty.
Master Sniper (35 points): Kill 10 enemies in a row with a headshot on any difficulty.
Need a Ride? (20 points): Meet up with the rescue team in Washington, D.C. on Normal or Higher difficulty.
Oh, the Humanity! (30 points): Destroy all the assault blimps at the Tower Bridge on any difficulty.
One Man Army (45 points): Kill 400 enemies in the campaign on any difficulty.
Presidential Citizens Medal (75 points): Complete the campaign on Hard difficulty.
Presidential Medal for Merit (35 points): Complete the campaign on Normal difficulty.
Presidential Medal of Freedom (100 points): Complete the game on Insane Difficulty.
Reservation for One (5 points): Make your way down to Hotal Langteau on Normal or higher difficulty.
Run! (25 points): Sprint for a total of 30 minutes throughout the campaign on any difficulty.
Save Yourself (25 points): Escape from New York on any Difficulty.
Sharpshooter (10 points): Kill all the paratroopers as you make your way down the skyscraper on any difficulty.
Stowaway (30 points): Sneak onto the Zeppelin on Normal or higher difficulty.
Swirly Time! (5 points): Drown a German in a toilet in the Tower of London on any Difficulty.
Turning Point (25 points): Complete the campaign on any difficulty.
TV Repairs (5 points): Smash an enemy's head through a TV in the White House on any Difficulty.
David and Goliath (30 points): Win a ranked match against someone 100 or more leaderboard ranks above you.
First Time for Everything (5 points): Finish a multiplayer game.
Killer (20 points): Get 100 ranked match kills in any mode.
Killer Instinct (30 points): Get 500 ranked match kills in any mode.
Maybe I Should Go Outside… (40 points): Get 2500 ranked match kills in any mode.
MVP (15 points): Win an 8-player ranked or player match in Team Deathmatch mode with the highest score.
Next Time Take the Stairs (5 points): Fall to your death during a multiplayer game.
One in the Chamber (10 points): Kill a player in a ranked match with the last bullet in a pistol clip.
pwnt (15 points): Finish an 8-player ranked or player match in Deathmatch mode with the highest number of kills.
Stayin' Alive (25 points): Finish a ranked match in Deathmatch mode without dying.
Team Player (25 points): Win 20 ranked matches in Team Deathmatch mode.
Uberdork (25 points): Win 5 ranked matches in Deathmatch mode.
World Tour (15 points): Finish a multiplayer game on every map in every mode.