Its jaws are welded shut to keep its ancient energy inside sealed. The small amount of energy that escapes is a match to the remnants of decimated ancient cities.
Thanks to its gargantuan jaws, which could shred thick metal plates as if they were paper, it was invincible in the ancient world it once inhabited. It is said that Golutrum were ordered to protect people and Pokémon by the ancient people who made them.