Killed by Arthur Ketch

Beings killed by Arthur Ketch.

Monsters

 * Countless unnamed monsters - Killed over the course of his career as an assasain for the British Men of Letters.

Vampires

 * An unnamed vampire - Decapitated after it was captured by the British Men of Letters.
 * Dozens of unnamed vampires in America - Killed with Mary Winchester during Project V.
 * Countless unnamed vampires - Killed over his career as an operative for the British Men of Letters.

Hunters

 * Eileen Leahy - Killed by Arthur's hellhound on his orders.
 * Six unnamed hunters - Killed by Arthur's hellhound on his orders.

British Men of Letters

 * Lady Toni Bevell - Slit her throat in the Men of Letters bunker.
 * Mick Davies - Shot in the back of the head with a silenced pistol on the orders of Doctor Hess.

Psychics

 * Magda Peterson - Shot twice with a silenced pistol on the orders of the British Men of Letters.

Regular Humans

 * Agent Camp - Throat slit on the orders of the British Men of Letters.
 * Pvt. Norton - Throat slit on the orders of the British Men of Letters.
 * Rick Sanchez - Throat slit on the orders of the British Men of Letters.
 * Six unnamed soldiers - Throats slit on the orders of the British Men of Letters.
 * D. Winters - Throat slit on the orders of the British Men of Letters.
 * Countless unnamed humans - Assassinated on the orders of the British Men of Letters.