Finding an official PDF for Arks of Omen: The Lion is difficult because Games Workshop (e-books or PDFs) for standard Warhammer 40,000 rulebooks or campaign supplements.
Expanded rules for close-quarters spaceship combat, featuring unique stratagems and enhancements. arks of omen the lion pdf link
: For the Boarding Action rules and character datasheets included in the book, sites like Goonhammer provide exhaustive reviews and mechanical breakdowns. Finding an official PDF for Arks of Omen: