In The Lion, The Witch and The Wardrobe (2005), all want summer and liberty whereas the White Witch wants winter and repression.
But the antag/protag may or may not know each other initially. In this instance, they will become aware of each other as each becomes more potent. In this instance, a variety of sub-antagonisms will be enountered, which will be obstacles to a series of sub-goals.
In Spartacus (1960), Crassus is barely aware of Spartacus until he starts defeating Roman legions.
There is an argument that opposing goals most directly converge in Act III, which is what leads to direct conflict.
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