antagonism
antipathy
antithesis
clashing
climax
collision
conflict
confrontation
contradiction
contradistinction
contraindication
contraposition
contrariety
contrast
counterposition
cross-purposes
disagreement
discrepancy
hostility
inconsistency
inimicalness
moment of truth
oppositeness
opposition
opposure
oppugnance
oppugnancy
perversity
polarity
repugnance
clincher
life-or-death
match-up
matchup
rematch
semifinal
shootout
slidewalk
tiebreaker
godown
hoedown
lowdown
slowdown