Mystara is a campaign setting that evolved from the B and X series modules. Mystara was the "default"
setting for the non-Advanced editions of D&D, and the Blackmoor setting was later placed in Mystara's distant
past.
o The Hollow World: Mystara is actually a hollow planet, and its interior is used as a time
capsule by various immortals who decided to preserve cultures from the outer world that were in danger
of extinction.
o Red Steel/Savage Coast: A swashbuckling-themed spinoff of the Mystara setting that revolved
around a magical curse that afflicted all characters. Red Steel was originally released as a boxed set,
but was later revised and released online for free as the Savage Coast. These were the only Mystara
products for AD&D.