Complete Left Behind

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

Win the water gun fight

Play the Jak X game in Left Behind

Survive all of Ellie's jokes

Collect all comics

Find all Firefly pendants

Pet Buckley the dog

Ride the sewer contraption with Henry and Sam

Pick up Frank's note after it's discarded

Find all workbenches

Upgrade and then break one of every melee weapon