New answers tagged science
The Deathgate Cycle, while leaning more toward fantasy, has some pretty strong elements of sci-fi as well. It's quite well-plotted, with excellent examples of satisfying character arcs and a cohesive plot that comes together over seven books.
M.Y.T.H. Inc. comes to mind, and possibly Dinotopia. H.P. Lovecraft's work, while more focused on horror, contains elements of both fantasy and science.
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