Edmund had the ability to control bullets,
though at his current rank of "human," he couldn't yet make bullets turn corners or compress their power and other advanced techniques. However, he could somewhat adjust the initial speed of the bullets as they left the gun barrel.
Ensuring they would penetrate the brain but not pass through... just letting the bullet stay within the brain tissue.
Moreover, these special silver bullets would compress the air upon impact, causing a small explosion, and make the silver liquid instantly fill the cranial cavity, achieving "Brain Purification."
However,
the old man sitting in front of the campfire had no reaction whatsoever.
Streams of silver liquid were even being expelled from his nostrils, causing no damage to the brain at all.
The old man continued barbecuing and even took the time to feed his pet dog, Mili.
Hidden in the shadows, Edmund's expression turned ugly, "Immune to silver? Is this one of the Moon Transformation's traits!"