Blightfall

Free at last from decades of war against their alien oppressors, Skyward Flight leader Arturo Mendez expects his first postwar mission to be simple: escort diplomats to make peaceful contact with an isolated pocket of humanity cut off since the war began. Instead they find a world half-swallowed by invasive forest and littered with drifting wreckage, where the promised reunion looks nothing like anyone hoped. Opens the Riftwake trilogy, set in the world of Sanderson's Skyward saga.