Devil May Cry 1 Enemy & Boss Strategies

Enemies:
1. Plasma - Weak against devil trigger grenade launcher combo. Activate your devil trigger and shoot your grenade launcher at him and it should in most cases one shot him. May take up to 3 though.

2. Phantom - Use the grenade launcher to fill up your devil guage and just Alastor's Air Raid him. Repeat this over and over until it is dead.

3. Frost - Weak against Ifrit. Use Inferno or just combo them in devil mode.

4. Nightmare - Make sure you have your devil trigger available at all times. Just use it to evade Nightmare's 1st attack. He will have orbs shooting at you. These are easy to evade. After orbs are done firing Nightmare will spin shooting spikes out at you. These are not easy to avoid. All you have to do is jump up in the air and trigger the devil mode using Alastor and hit LB to stay afloat in the air and avoid Nightmare's spikes. Now undo the devil trigger and hit the orb on Nightmare's back. This will refill your devil guage. The second attack  will try to fool you. Nightmare will expose the orb in its rear area, but it will fire 4 homing vollies at you soon after. Avoid them and then hit the orb. Repeat this process until successful if you do get sucked in into Nightmare's void you will have to fight a Phantom boss. This boss is easy just shoot it with the grenade launcher to fill up your devil guage and spam Alastor's Air Raid. Repeat until Phantom is dead. Nightmare has another attack where it shoots a frost beam. He will expose his orb when he does this. Just make sure you are not in front of him when he does this. Also when you are on top of him do not fall off or he will spin violently and get you with the frost beam.

Nightmare (2nd encounter) - This time around he exposes his orb on top of his body, but also releases a rotating bar that spins around his body. This thing is dangerous. All you have to do when he does this is double jump up in the air and press Y. Hit it twice and it will go away. This time around you encounter Griffon inside the void. Just use Ebony & Ivory (pistols) with Ifrit. You should take him out easily just avoid his projectile attacks.

5. Shadow - Use the Handgun Ebony & Ivory comb and shoot like crazy. Try to double jump of a wall and keep shooting whilst in the air. Once it exposes its orb use Ifrit devil mode and combo it once. That should do the trick. Now stay away from it and  double jump off walls till it explodes.

6. Nelo Angelo (3rd encounter) - Use Ifrit to counter his sword projectile attacks and use the Ifrit devil trigger to combo Nelo. Also use Inferno on him works well.