Mission 19 - Vergil
Finally, the penultimate mission of Devil May Cry 5 - Mission 19 - Vergil - sets Dante up against Vergil. This page covers how to fight Vergil, and how to prepare, and is part of the DMC5 Walkthrough.
Make sure you have at least one Gold Orb on hand before starting this one. Vergil is easily the most difficult fight in the game, and he's no pushover.
Some things to keep in mind: Vergil will block your bullets unless he in incapacitated, so don't bother shooting projectiles unless he is otherwise indisposed. Use normal Devil Trigger to heal - you will probably need to - but be aware this is at the cost of Sin Devil Trigger, which deals more damage.
Vergil's main tell before attacking is in the image above - he holds his hilt. He'll attack with one of two attacks. He'll either rush at you, or send a ball of energy your way. Either way, continously dodge (or jump) left or right to avoid this attack.
When he has these blue blades around him, avoid getting too close. They will inevitably hit you - so wait until the dissipate, but be ready to dodge from afar.
If you keep hitting Vergil with the same weapon, he'll learn your attack patterns and begin deflecting you. Change up your weapons and styles to keep the pressure on. We found approaching on the Cavaliere in Swordmaster mode with B/Circle to be quite effective.
Vergil will activate his own Devil Trigger during the fight. If you're able to, activate Dante's Sin Devil Trigger at the same time to continue doing damage, Otherwise, you'll be forced to play defensively by continuously running, jumping, and dodging until he reverts to his normal human-like form. Really, just keep moving unless you're extremely confident.
If you see this circle of flame, get out immediately. This attack does massive damage, and unless you have a substantial amount of health left, it may very well kill you.
Finally, once you've just about got him down to a sliver of health, a cutscene will play. But before Dante and Vergil can clash one last time, a stranger (or is it?) stops them.