From publisher blurb:
The Grand Stair stretches behind the scenes of the multiverse,
...the Doors upon its unfathomably vast span leading the way to gossamer worlds of limitless variety and infinite possibility. On one of these worlds, you can ride a t-rex with power arms. Giddy-up!
Aethersaur Island is a gossamer world formed in the wake of a calamity of cosmic proportions – the catastrophic convergence of three realities into a single strange and savage land. Now, the prehistoric wilds holds patches of civilization carried over from an Edwardian-era Earth, alien obelisks attract gibbering troglodytes to the edges of the tar pools, and a triceratops-headed Umbra Master cackles maniacally from his erupting volcano lair. To survive, intrepid steampunk heroes must grapple with science past the edge of reality, using the mysterious power of the aether to harness the island's terrible lizards. Come meet the aethersaurs, and saddle up a steam-powered cyborg t-rex of your own!