OSR Commentary & Review The Book of Valkyries, published by Night Owl Workshop For Old School Campaign

 The Book of Valkyries, published by Night Owl Workshop (authored and illustrated by Thomas Denmark), is a 108-page supplement designed for the Original Fantasy RPG and compatible with a wide range of OSR systems.

Released in late March 2026, it serves as a companion to Denmark’s previous work, Norse Beasties, providing deep lore and mechanical integration for the demigoddesses of the Norse sagas.

Key Features

• 43 Unique Valkyries: The book details 43 individual shieldmaidens of Asgard, moving beyond generic stat blocks to provide specific descriptions and roles based on mythological research.

• NPC Class: It includes a specialized Valkyrie non-player character class, allowing GMs to use these figures as more than just monsters. They are framed as divine emissaries, guides for heroes, or "choosers of the slain."

• Hand-Drawn Art: Staying true to the publisher's aesthetic, the book is lavishly illustrated with hand-drawn art by Thomas Denmark, created without the use of AI.

• Compatibility: While designed for "Classic D&D/AD&D" styles, it is explicitly noted as compatible with:

  • Old-School Essentials (OSE)

  • Labyrinth Lord

  • Swords & Wizardry

  • Adventurer Conqueror King System (ACKS)

  • Colonial Troopers / Guardians / Warriors of the Red Planet

Product Specifications

Feature	Details
Format	Digest-sized (5.5" x 8.5")
Page Count	108 Pages
Pricing	~$6.99 (PDF), ~$19.99 (Softcover)
Author/Artist	Thomas Denmark

Campaign Integration

The supplement is designed to be "plug-and-play." While it leans heavily into Norse Mythology, the entries are written to function as high-power divine agents in any epic fantasy setting. They can serve as powerful patrons for high-level characters or as existential threats on the battlefield for those who would defy the gods' will.

 The Book of Valkyries, brings a touch of the divine into the focus of an OSR campaign setting. And does so with easy to use clarity and divine inspiration for adventurers with a Norse focus. The supplement is well written and has some incredible artwork. The Book of Valkyries is actually incredibly useful if the DM wants to use these divine messengers as the go between for Norse clerics and their gods. 
For a game such as Adventurer, Conqueror, King 2nd this supplement brings a great set of divine NPC's for your campaigns. It's well written and these NPC's are well written and are perfect for tweaking or even destroying adventurers in equal measure. These are great NPC's for using adventure hooks to get the PCs involved with them. 
For Castles & Crusades these NPC's are both nasty and highly motivated to get involved with adventurers. They have agendas and goals for those that they interact with. I highly recommend,  'The Book of Valkyries'.