Careless sacrifice and futuristic fantasy (3-2)

I believe the answer is:

sci-fi

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'fantasy' is the definition.
(I know that sci-Fi is a type of fantasy)

I don't understand the rest of the clue.

(Other definitions for sci-fi that I've seen before include "Doctor Who genre" , "Literary 7 down" , "Space opera genre" , "Literary genre (abbrev)" , "Isaac Asimov genre" .)

I've seen this clue in the Sydney Morning Herald.

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