Eberron Jumpchain

From the introduction:

Welcome to the wonderful world of Eberron! Twelve moons hang in the sky, with a belt of shattered rocks suffusing it. The twelve Dragonmarked houses rule over all aspects of life, each sponsoring a member of the Twelve, wizards dedicated to keeping the peace. Swashbuckling rogues work alongside ingenious craftsmen, wielding swords and shield and automatic crossbows. Robotic soldiers, remnants of the last great war, tread the streets, living the closest they can to normal lives, albeit typically normal lives as mercenaries. Spellslingers craft works of true arcana, ships that travel the sky, trains fuelled by lightning, and stone tablets that can communicate over great distances.