The Ransom Knight (World of the Demonsouled short story)

Once banished by his father, Mazael Cravenlock is now a knight in the service of Malden, Lord of Knightcastle. When Lord Malden sends Mazael to ransom a nobleman from a bandit of the hills, he suspects there is more at stake than a simple kidnapping.

He's right.

When dark magic stirs in the hills, Mazael will need all his wits and courage to escape an army of malevolent ghosts...