Here is the full list of all 28 Organ Trail: Director's Cut achievements.
Kill 500 zombies
Always choose to shoot your way through zombie hoardes.
Your party dead, you made it to Safe Heaven alone.
Put down an infected party member who has passed out.
Get attacked by zombies 20 times during scavenging.
Find your own grave.
The station wagon breaks down 4 times during the trip.
Successfully forde a horde of zombies 3 times.
Kill 25 zombies without missing a shot.
Stop at 50 tombstones.
Beat the game on hard.
Scavenge more than double the supplies you can carry.
Don't pull the trigger
Make it to Safe Haven with George Romero in your party.
[Secret] sacrifices himself for the greater good.
Fully upgrade your station wagon.
Survive all 3 boss encounters.
Investigate 30 points of interest.
Use 50 medkits
Someone died of dysentery.
Have $1000 on you.
Beat the game without trading anything on the road.
Kill "Ryan" at the start of a game.
Make it to Safe Heaven without starting with any money or selling anything.
Become a zombie.
Make it to Safe Heaven without starting with any food or buying any food.
Beat the game five times.
Kill all the other members of your party while they are healthy.