Completion bonuses:Complete Campaign mode to unlock new difficulty levels, options for infinite ammo, infinite grenades, double health regeneration, and the character, environmental, and weapon concept art at the “Extras” menu.Achievements:ACHIEVEMENT – HOW TO UNLOCKClingy (25 points) – Kill 15 enemies in a row by grappling them.Combat Veteran (25 points) – Kill 250 enemies in the campaign.Compat Experience (10 points) – Kill 50 enemies in the campaign.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.Exploding Monkey (20 points) – Kill at least Four enemies with one explosion.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.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.Master Sniper (35 points) – Kill 10 enemies in a row with a headshot.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.One Man Army (45 points) – Kill 400 enemies in the campaign.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.Save Yourself (25 points) – Escape from New York.Sharpshooter (10 points) – Kill all the paratroopers as you make your way down the skyscraper.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.Turning Point (25 points) – Complete the campaign.TV Repairs (5 points) – Smash an enemy