The following page of our guide to Devil May Cry 5 describes a boss fight with Malphas. The female boss is quite strong and can inflict a lot of damage.
Malphas in Devil May Cry 5
Where to find it: Mission 15 - Crossroads: Nero
Malphas creates spikes, jumps with its mount, and escapes the arena using teleports. This boss can get on your nerve because even when you get close to it, you'll be under constant attack.
Try not to stand right next to the boss and be sure to equip yourself with the Gerbera, which will allow you to avoid many of the attacks. You need to stay very mobile around Malphas because her attacks deal massive damage. In the meantime, use ranged weapons to hurt the enemy from a distance.
At some point, the boss will disappear completely from the screen and you will be attacked with claws that emerge from random places. Avoid the blows and be sure to avoid the big, falling attack, which the boss will perform at the end of the combo.
When you deal a little damage to Malphas, her horse will fall unconscious and you'll have a minute to deal a lot of damage to the boss. At the end of the battle, the boss will start reviving - attack it while it's busy.