Collect all trophies
Complete Part 1
Break into every locked door using shivs
Find all workbenches
Open All Safes
Find all workbench tools
Upgrade and then break one of every melee weapon
Find a Firefly pendant
Find one training manual
Find a comic
Craft every item
Pick up Frank's note after it's discarded
Complete Left Behind
While in stealth, turn off the spotlight generator in Pittsburgh.
Ride the sewer contraption with Henry and Sam
Leave Ellie hanging after a job well done
Pet Buckley the dog
Played the Jak X game in Left Behind
Win the brick throwing contest
Defeat Black Fang without getting hit
Win the water gun fight
Use bricks or bottles to lure an infected into attacking a human
Find all Firefly pendants
Collect all comics
Find all notes and artifacts
Engage in all optional conversations
Survive all of Ellie's jokes
Find all training manuals
Fully upgrade a weapon