The first step is to unlock the
Sling Rot blueprint, located in
Old Town on the steps of the church. You'll also want to unlock the entire bottom row of skills in the
Brawling section.
Now make the
Sling Rot vehicle combo. You can find it directly in front of the church near the blueprint or on the highway leading to the bridge behind it. Once inside the vehicle, you will be preforming a 3 part loop over and over again as follows:
After you complete the third part, get out of your vehicle and make a new one; then repeat the process.
A couple of notes:- Use your special ability as often as possible as this generates most of your kills.
- Keep an eye on your vehicle damage. You don't want to ever have less than 30% without being near one of the two spawns.
- The 3rd part of the loop is essential as triggering the checkpoint on the highway allows all the zombies in
Old Town to respawn.
- The full 3 part loop should take 3 minutes.
- The counter in the bottom left is a little off; usually about 1%-2% from the achievement counter.
This method generates
36,000+ kills/hour. You can grab this achievement starting from 0 in less than 2 hours.