Maze Knights

From the introduction: Maze Knights is set on Wreckworld, a shattered, overgrown planet strewn with the wrecks of vessels from innumerable civilizations and planes of reality. The City of Mazegate is the party's home base, a thriving metropolis of wreck survivors shielded from danger by scavenged magical artifacts. All magic on Wreckworld is powered by mana, a mineral found in monsters, magical artifacts called relics, and underground veins. The PCs are adventurers with their own mana-powered airship, scavenging in the ruins for mana and useful artifacts.