I tried Briskbreeze with a group that fell apart. So I tried to solo. Here's a couple of observations that might make your job easier, regardless if you solo or not.
1) When the mobs eventually return the tower, you can skirt the wall (hug it!) to go around them. The stairs up do not re-lock, and you won't automatically get dragged in if you hug the wall.
2) Angrus Hollowsoul does not cast more than three Exploding Ember minions. If you can kill them in three rounds as they get summoned, you can go back to concentrating on him.
3) The room with the green orbs has been addressed elsewhere, but for sake of convenience, don't touch the green orbs. You have to get the blue orbs to continue, so approach the blue orbs from the wall facing toward center. Approach each blue orb slowly until you pick it up, then back out towards wall and re-position to get the others.
4) Orrick Nightglider doesn't necessarily cast his cheat spells on a set order. His Heck Hound may go off three turns after his last, and his Meteor Strike can also be on either a three or four turn count. I've had him cast both cheats on same turn. As well, he doesn't always cast Meteor Strike as second cheat. It was mentioned that he may drop an improved Tower Shield, and he may also cast a Fire Elf (shield breaker!).
Here was my deck arrangement when soloing Angrus: 5 Fire Prisms, 5 Fire Shield, 5 Helephant, 4 Giant, 4 Fireblade, 4 Amplify, and 1 Reshuffle (from Amulet). I continuously kept up a Fire Shield, and built up, saving my prisms for when he summoned the Exploding Embers. I'd kill the Embers either on the turn after they came out or the following. After three were down, I just went after Angrus. Had I known, I may have ran four Helephants, and two Genies (now that I have them). I didn't even wind up using the Reshuffle, but it was there for insurance.