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king; monarch; ruler
champion
王者に挑む気概が感じられた。
You could sense the spirit of someone challenging the champion.
王者らしい堂々とした戦いぶりだった。
It was a commanding performance worthy of a champion.
三連覇を達成した選手が不動の王者として認められた。
The athlete who achieved three consecutive titles was recognized as undisputed champion.