Zerg Rush Google Easter Egg
This easter egg is referring to the game StarCraft 2 by Blizzard. There are three fractions in StarCraft 2: Protoss, Terran and Zerg. Imagine the Zerg like aliens. Zergs have a unit called "the Zergling" which is a small creature that usually attacks buildings and enemy units in groups. If you have a lot of Zerglings and run to your opponents fast this can be called "a Zergling rush". There are also custom maps that you can play that are called Zerg Rush: You are in the middle of the map and Zerlings are streaming to your bade from all sides. You have to defend it like in the easter egg.