This page offers a guide on where to locate and how to complete A Blood Hymn for Edmund, which is a Mystery located in East Anglia.
This Mystery is located directly beneath the synchronization point, Edmund’s Hope. Head through the tower’s archway and speak to Aelfwyn who has murdered a bunch of men. Luckily for you, she is not a boss fight, so you won’t need to prepare for a tough battle. Just parry her attacks to reduce her stamina then stun attack her to defeat her. Speak to her again before she dies to complete the quest.
Before you head away from this area, you should grab the key on the upper platform of the tower and then use it to open the door to the building down the path. Inside, you’ll find a Treasure Hoard Map.