From publisher blurb:
From limitless worlds arise uncountable threats, from hordes of faceless enemies to powerful archons of intrigue and conspiracy.
Echoes of the Typhonians reveals a threat that extends across countless worlds, one that has until now gone unnoticed. As one antagonist rises, another remarkably similar foe emerges in a distant world. One after the other, these individuals make their presence known, forming plans of their own devising — yet as one grows in power, another vanishes as suddenly as he appears. Mighty generals, world-shaking sorcerers, and timeless librarians, each with one thing in common: a unique destiny that may bring ruin to the Gossamer worlds and all who hold them dear.
Echoes of the Typhonians includes new rules, story hooks, and campaign suggestions centering around the Usari, a mysterious race that may hold the keys to the ancient secrets of the Typhonians. Who are they, and what is their ultimate fate?