The Temple of Persephone

When the boat lands, start using Charon's Wrath on the enemies that appear. As it did for you, it stuns them and causes them to bounce around while taking damage. Try knocking enemies up into the air with your Blades of Chaos, then targeting them with Charon's Wrath in mid-air. It's fun!

Save your game and head into the temple here. There are two catch-up chests in the first room, so nab the orbs inside and head up the stairs. There's a fairly close-quarters battle here with more of the devil-dogs that you faced before and some grenadiers. Holding down the L button to guard while periodically using your square attack with the Gauntlet seems to be a good strategy to weakening up the devil-dogs. You can also use Charon's Wrath to lock up large numbers of enemies, if you like.

When you finish off your foes, nab the Red Orb Chests and the catch-up chest hidden by the camera on the bottom and right sides of the area, then head upstairs to the closed door and use O to open it. The next large room will feature a number of masks and a horde of easy enemies. Use Charon's Wrath to lock up the enemies (it's easier if you've upgraded it once) while using the L+square attack with the Gauntlet on the masks to break them. (If you've fully upgraded the Gauntlet, then the Olympic Thunder aerial attack, which can be performed by jumping over a mask and holding L+Triangle, is even better.) Keep moving here; if you're caught in one of the green beams here, you'll probably be petrified and killed.

Chasing Calliope

The next big fight will consist of first one armored cyclops, then two cyclopes, with harpies filling in for the annoyance factor. Stick with the Blades of Chaos here, wear off the cyclops' armor, and hit them from long range with normal attacks while dodging away from their blows. After a while you'll be able to minigame them to death. You can either use Charon's Wrath on the harpies or devote some of your attacks to them while you're safe from the cyclopes.

When you're done, open the door to the north first to find some chests, then open the door on the eastern side of the area to head upstairs after Calliope. Another mask room awaits. Use Olympic Thunder if you have it to clear up the area a bit, beat the enemies, and move on.

The next large area will have more armored minotaurs. You can use any armor-breaking attacks to defeat them, but the aerial Olympic Thunder move works pretty well for wearing them down after the armor breaks. You'll still be vulnerable to their charge attack while you jump, but most of their other attacks will swing below you harmlessly.

After defeating the minotaurs, move to the crank platform in the elevator shaft nearby and start cranking yourself upwards. There are broken bits of the wall that can be smashed to find items and enemies, as well as a whole doorway that will lead you to a catchup chest. There's another gauntlet at the top of the area, with some new Gorgons that will attempt to coil themselves around you and petrify you, which will probably result in a quick death in this area. Use either Charon's Wrath or aerial Olympic Thunders to keep yourself clear of enemies. When they die off, an armored cyclops will appear. Kill it to drop the barriers in the doorways here. To the east, you can find a couple of chests, while the northern exit will feature another save point.