Here is the full list of all 10 Steampunk Graveyard achievements.
Complete 1 Graveyard
Complete 3 Graveyards
Complete 6 Graveyards
Complete 9 Graveyards
Complete 12 Graveyards
Kill 100 Zombies
Kill 200 Zombies
Kill 300 Zombies
Kill 400 Zombies
Kill 500 Zombies