The opposite of synergy - The idea that combined parts have properties that are more or less that the sum of the parts. The negative-sum version is sometimes called dysergy, leaving synergy to mean only beneficial effects.

note. i am not entirely sure if the usage in the example provided is right, as it is a very uncommon word, but submissions require an example so i'll give it a whirl.
the heros fought against each other in dysergy.
by vodka June 3, 2004
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