In a bloody manner; with much blood, violence, or gore involved.
From 'bloody' (Old English blōdig) + adverbial suffix '-ly' (Old English -lice); follows standard adverb formation.
Medieval battle accounts use 'bloodily' constantly in ways modern readers find almost comical—'the battle ended bloodily' appears in countless chronicles, yet modern historians can tell which ones were actually there and which copied from earlier, never-seen-battles.
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