They Are Billions

You’ll probably be close to this by the time you’ve done all the other achievements, I was on 96% by the time I only had this and the 1million kills achievements left.

I found the best way to have a relatively easy run with lots of zombie deaths was to play on The Peaceful Lowlands on 120 day duration, with nightmare population.

This should give you plenty of time to build a solid defence, as it is the easiest map for fast expansion, the doom villages provide plenty of zombie fodder too.

Each run will net around 45000 zombie kills, but by the time you are going or this you will likely find this map with these settings pretty straight forward without imposing any play style restrictions on yourself.

- focus on growing population and the economy
- reload if after initial scouting you don’t like the map
- expand with ballista
- skip rangers, go straight to soldiers
- once you have ~30 soldiers it’s time to aggressively clear the map while continuing to use ballistas to expand your border
- park two ballistas outside a doom village and use your soldiers to bait the residents into them
- a squad of 8 titans can chew through pretty much anything, great for speeding up the time it takes to mow down the waves