Curly rushed her antagonist, who struck again and leaped aside.
He saw the silent circle, with gleaming eyes, lolling tongues, and silvery breaths drifting upward, closing in upon him as he had seen similar circles close in upon beaten antagonists in the past.
He was in a savage temper, and, standing over six feet from the ground, was as formidable an antagonist as even Buck could desire.
Skeet and Nig were too good-natured for quarrelling,—besides, they belonged to John Thornton; but the strange dog, no matter what the breed or valor, swiftly acknowledged Buck’s supremacy or found himself struggling for life with a terrible antagonist.
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Show samples from other sources
She is my forever antagonist.
Gillian Flynn -- Gone Girl
They could have done him no real harm, of course, but the shock and pain of having a number of his toes nipped simultaneously by an unknown antagonist must have been considerable.