Uh, mashing sword in front of Phantom 1's face will get you killed really easily. You need to jump slash his back for your primary way of dealing damage. Only time I'd consider attacking his face would be to Stinger his fireballs back to him.
The optional fights with Phantom where he chases you down a hallway and you can escape are really easy, though. The timing to reflect his fireballs isn't too hard to get down. Only problem will be the camera trying to point you to the escape door instead of Phantom. Plus, if you have Air Raid, he's *completely* free.
Devil Trigger's length... well, I'm stating the obvious here but it changes a lot with how many runes/purple orbs you have. When I had the 3 default runes it was pretty damn short, but it feels like I have a good amount of time in it with 5 runes. It does recharge pretty damn fast, though, especially if you can find a place to taunt.
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