Getting a Fumigator
In order to start this easter egg, you will need to pick up a fumigator. There are four of these around the map.
Growing the Pods
Once you have a fumigator, you can interact with any of the green plants that are scattered around the map at all of the locations except for the cosmodrome. Doing so will cause the zombies to attack the plant and also cause special purple eyed zombies as well, which will despawn after the egg finishes.
You need to protect the plant from the zombies who will destroy the plant if they are allowed to hit it too many times. If you successfully defend the plant for enough time, it will break open and give you rewards like points, salvage, weapons, equipment, aether tools, and pack a punch crystals.
These pods will respawn every round and sometimes even multiple times a round and there is no limit to how many you can do, so feel free to farm them as much as you like.
Using Toxic Growth
You can increase the chances of getting better rewards, like aether tools and pack a punch crystals, by using a charge of the field upgrade Toxic Growth on the pod. Just one charge can last for several rounds if you don’t let zombies touch it too much, so you can farm multiple instances of the same pod using just one Toxic Growth use.