Gaster has the powers of  Acausality, Immortality (Unknown type due to his nature as both existing and not existing simultaneously), Possible Possession (Depending on whether or not he possessed Monster Kid or simply created a duplicate of them), Omnipresence, Spatial Manipulation (Created a new room between two point that were previously right next to each others, and erased it afterward), Possibly Void Manipulation (Possibly completely erased one of his followers) he can summon his invention called the gaster blasters he can use teleportation and herobrine has the powers of Flight

Teleportation Electrokinesis Possession Immortality Invisibility Stealth Strength Speed Causing blindness

Herobrine is also known to spawn pigs without eyes and choping down trees and setting them on fire so this match will become a draw beacuse each one is immortal.