Herobrine's Cavern is a cave that contains many command blocks, which are designed to do Herobrine's pranks in The Phantom Virus, and cover all the villages in lava. It is Shaivalak and Reaper's job to guard it.
The cavern begins creating the pranks, and Gameknight and his friends are forced to run around and clean up after it. Eventually, they discover its location in Olympus Mons and go there to destroy the redstone. The Command Block Battle takes place, and Reaper and Shaivalak are destroyed. At the last second, Gameknight changes the id from lava (10) to sunflowers (175) and saves the villages.
- The Phantom Virus (First Appearance)