Vergil 3 tactics (As far as I remember)
Keep shooting him with Ebony and Ivory while you're not slashing him (miniscule damage but trust me it piles up and somehow he devil triggers less). Stinger him to close the distance and switch to either Beowulf or Cerberus and combo him until he devil triggers. When he DTs you should DT as well and keep pounding on him. When his DT wears off still keep pounding until he retreats. Use Trickster class to dash and close the distance. Stinger. Switch. Beowulf. Combo him to oblivion.
If you're still having trouble. Buy a ton of Vital Star L, that way you're virtually invincible.
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