Engage in all optional conversations

Find all training manuals

Break into every locked door using shivs

Use bricks or bottles to lure an infected into attacking a human

Defeat Black Fang without getting hit

Win the brick throwing contest

Find all workbench tools

Upgrade and then break one of every melee weapon

Leave Ellie hanging after a job well done

Fully upgrade a weapon

While in stealth, turn off the spotlight generator in Pittsburgh

Find a comic