The Milkhemist

[Downloading the game is highly recommended to reduce lag.]

Play as a plague doctor from the middle ages, where a calcium deficiency has turned everyone to zombies. You have discovered that milk is the only way to bring them back from the dead.

The goal is to shoot zombies with milk to turn them into humans, while also protecting the humans from getting bit and turning back into zombies.

You can use the money you earn to buy new guns in the shop, which will allow you to tackle harder levels. If you make it far enough, you can take on the brutes...