Here is the full list of all 21 SurrounDead achievements.
Take out 500 zombies with one character.
Take out a zombie boss.
Gain access to a secure area.
Catch a fish.
Traverse for 10km with one character.
Break a bone from a high fall.
Cause the death of your player.
Take out a human survivor.
Find & drive a vehicle.
Use a medical item on the player.
Place down a buildable.
Play 'Survival'.
Play SurrounDead during Early Access release.
Traverse for 100km with one character.
Take out 5000 zombies with one character.
Take out 100 human survivors with one character.
Gain access to a hidden secure laboratory.
Take out 10 zombies bosses.
**REDACTED**
Take out 50 animals.
Take out 200 animals.