Logarius is an optional boss that Lords over the, also optional, area Cainhurst Castle in Bloodborne. Before you even initiate this fight, make sure that you equip the Knight armor found in Cainhurst en route to Logarius, as this will increase your blood defense significantly. My best advice is to just treat this boss with the same dodge, hit, dodge strategy. When you are close be mindful of his close range spells and always try to dodge to Logarius’s right side, your left. Good luck hunters and long live the Vilebloods!
Bloodborne Bosses: Martyr Logarius Strategy