Cassandra, Eeyore, bitter-ender, brawler, calamity howler, cynic, defeatist, defendant, diehard, disputant, dissentient, dissident, filibuster, filibusterer, frustrater, hinderer, impeder, intransigent, irreconcilable, killjoy, last-ditcher, litigant, malist, marplot, naysayer, nihilist, noncooperator, objector, obstructer, obstructionist, obstructive, opposer, oppositionist, pessimist, plaintiff, prophet of doom, protester, quarreler, resister, retreatist, scrapper, seek-sorrow, thwarter, worrywart, wrangler

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