What Canadane said. Use the combo on him many many times. You can mix in the mine attack about once a min to help. You can turn on the pyretic booster to help. But keeping the combo rolling is super important. Beyond that, the biggest time waster is when the bits appear. When they do go to the end of the line, target the far one if you can(or at least one farther in), and use the beam. This angle, if set up right, should clear out the entire line(or at worst, all but one or two at the far end). Then go to the other line and do it again. That gets rid of all the adds in 2 attacks rather then a couple dozen. Then in the last phase you can either do this again or ignore the bits, while you quickly combo down the lions to drop the shield. Then sword swings to finish.
