The Citadel is an archive of information for George R.R. Martin's A Song of Ice and Fire.
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Tyrion has been trained at arms, insofar as he could be in view of his handicaps. And he always goes into battle well mounted, well armored, leading men, with a personal protector close at hand (Bronn on the Green Fork, Ser Mandon on the Blackwater). Nonetheless, he is wounded in one battle and nearly killed in the other. He can hold his own in the chaos of battle, for a time at least, but that does not mean he is an especially skilled fighter... that distinction belongs to his brother.
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