Level-up your first weapon
Complete 5 locations of the Suburbs Area
Complete 5 locations of the Farm Area
Complete 5 locations of the Golf Club Area
Complete 5 locations of the Industrial Area
Complete 5 locations of the Downtown Area
Make 2 headshots with one shot
Kill 500 Zombies
Place 7 headshots in a row
Kill 5000 Zombies
Kill 10000 Zombies
Make 2000 headshots
Complete 10 Overrun missions
Kill 400 zombies with the crossbow