On the opening day of Gen Con 2000, Third Edition Dungeons and Dragons was unveiled. That same day, Necromancer Games released The Wizard’s Amulet, more or less the second OGL/D20 adventure (that’s another discussion).
Necromancer, working with other companies such as White Wolf, Judges Guild and Kenzer and Company, became one of the most successful d20 companies. Their mega dungeon, Rappan Athak, is one of the best known Third Era adventures.
However, the advent of Fourth Edition spelled doom for Necromancer. Co-founder Bill Webb founded Frog God Games, a clear successor to Necromancer, and they published products for Paizo’s Pathfinder. Frog God produced new items and also updated old Necromancer goods as well, Pathfinderizing them.
With the advent of Fifth Edition D&D, Frog God is now publishing for both lines (in addition to retro-clone, Swords & Wizardry). Necromancer and Frog God adventures and supplements had loosely been connected in that they took place in Webb’s personal campaign world.
Frog God is currently putting out that campaign world under the moniker The Lost Lands. It is going to incorporate nearly everything produced by Necromancer and Frog God Games. Some products, such as their Judges Guild updates and the Hex Crawl Chronicles, belong to other folks and won’t be included. But if you look at the long list of products, there’s an awful lot, including Gary Gygax’ under-appreciated Necropolis.