Find a shortcut

Complete 100 parries

Defeat a boss

Complete 20 parries

Spend 10 Exo upgrade points.

Complete "Fission."

Complete "Traffic."

Complete "Atlas."

Spend your first Exo upgrade point.

Complete "Induction."

Paint 10 enemies with a single threat grenade.

Prevent the walking tank from being destroyed by the Drone Swarm in "Induction."

Escape the German assault

Get a scoped headshot over 150m

Snipe an enemy through his eye

Cause a rocket sentry to destroy its own rocket when the rocket has been redirected back towards it.

Find the chicken's test results.

Dissolve a turret.

Knock a turret over with a security camera.

Trap yourself in a test chamber so that GLaDOS has to help you continue.

Silent Assassin: Perform a successful headshot

Silent Assassin: Perform a successful kill

Complete memory sequence 12.

Complete memory sequence 11.

Complete present day mission 4.

Complete memory sequence 10.

Complete memory sequence 9.

Complete memory sequence 8.

Complete memory sequence 7.

Fail a mission

Do a barbell curl or benchpress at any gym

Complete Big Smoke

Cleared Prologue: An Army Without Borders.

Break the Announce Table with an OMG Move (Single player).

Complete your first minefield.

Receive mention in Hero Pop-up in a Quick Match or Co-op mode

Complete all of the tutorials

Get 1 victory in any game session

You boarded the train and escaped the Chicago PD

You located the hotel room number 899

Unlock a technique

Achieve the rating: Silent Assassin

Remain undetected in a whole checkpoint

Complete 10 challenges

Blend in successfully

You fulfilled Birdie's contract and eliminated The King of Chinatown

Achieve your first accident kill

Hide a body

Subdue a person

Play an online game