I've played Tomb Kings for a couple years now, and they are a difficult army to learn to play. My experience has been that animated constructs are large fire magnets and tend to die quickly. When I tried using constructs my friends tended to wipe the board with me. Your infantry are gloriously cheap (points wise). Use that. And like the Vampire Counts, Tomb Kings live or die by the magic phase. If your opponent brings out Dwarfs, just flip the board and go home.