Echo and Gauntlet
Start with a nasty magical strike force that works for the Crusader. Continue in a supernatural landscape that speeds their magic. Finish with campaign hooks, the implications of a ruined world that exists alongside the world, and a possible origin story for the Crusader.
Echo & Gauntlet is the tenth installment of 13th Age Monthly Vol. 1. You can buy it as a stand-alone PDF, or purchase the collected Volume 1 to get all 12 issues plus the Free RPG Day adventures Make Your Own Luck and At Land’s Edge!