Complete Left Behind

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

Play the Jak X game in Left Behind

Defeat Black Fang without getting hit

Survive all of Ellie's jokes

Complete Part 1

Find all Firefly pendants

Clear any level with 4 Lives modifier.

Dance to 3 songs from Quick Play

Find all training manuals

Upgrade and then break one of every melee weapon

Leave Ellie hanging after a job well done

While in stealth, turn off the spotlight generator in Pittsburgh