The Path of Eos
Use the head in the tunnel to show enemies. Then beat them to a bloody pulp. Repeat.
GORGON EYE #6
Kind of hidden back from the Save Point is an item chest with a Gorgon Eye in it.
Continue on the path fighting more soldiers in the dark until you come out onto an open area with some Harpies. Use the head at the end of the path to open the wall to continue.
PHOENIX FEATHER #4
When you get to the hand over hand rope. First climb down to get a Phoenix Feather.
You'll get attack on this rope also. Just keep pressing forward. Then a jump up and some more fighting in the dark. Then a double jump glide over the large opening area and you're finally back in the light. After the scene take a Harpy ride over to the top of the wooden structure. Jump off the far right side to a side ledge with 2 Red Orb chests. Then head down the left side on the vines to get some more Red Orbs.
A new enemy appears in the form of the dual bladed Wraiths. These guys have the added fun of burrowing under the ground and then launching themselves at Kratos. The secret to these guys is combat grappling. Just keep grabbing them and launching them all over the area and follow it up with some heavy attacks. They will go down soon enough.
GORGON EYE #7
At the top with the Health and Magic chests use Helios' Head behind the scaffolding to reveal a hidden area with a chest containing a Gorgon Eye.
Charge a fire arrow before going out on the ledge as a quick placed shot to the bramble pots can eliminate the archers quickly. Then its back to grapple fest with the Wraiths. When you get to the top with the save point and the giant chain there is another hidden area with Red Orbs on the north wall. Then prepare for a flight. Jump onto the center vent and you'll be in a flying dodge fest.
The Chain of Balance
Keep to the chain and just move around it to get to clear spots. Once you get used to it, it's not that hard. You'll have a Context Attack on a Titan when you get to the end of the first flight section. Yes, that's right, the first section.
Now the path is crumbling beneath you and you need to get moving. Some double jumps and then a climbing section. Be careful of the falling rocks. Some more double jumps followed by a grapple and then a grapple to a LONG climbing section.
PHOENIX FEATHER #5
As you get off the ground will appear shaky but it will hold. Use Helios' Head to make an item chest appear to get the next Phoenix Feather.
Now flying section part 2. Much much narrower. Again stick to the center and watch far ahead for the small openings you are going to have to navigate through. There are some falling rocks at the end and then you are through.
MINOTAUR HORN #5
As you land on the giant box there is an item chest in the corner.
The use a flame arrow to free the bramble and get this giant box a moving. Then sit back and enjoy the ride because it's going to get crazy pretty fast. When the box stops grapple up to the small platform then double grapple back to the top of another box. Another flame arrow and you are on your way. The coming battle is going to involved a lot of minors and 2 sets of 2 minotaurs that are going to be trying to break the chain and send you all to your death. The key is to let the minors live. Simply run around and avoid them until the Minotaurs show up. Then use the minors as battering rams with your grapple to send the Minotaurs over the edge without even having to fight them. This will keep the chain intact and you alive the easiest. Remember there are two waves so keep as many minor enemies alive as you can. Then there will be some archers and a Cerebus. When you take control of Cerebus four more Minotaurs will appears and you need to use Cerebus' flame attacks to eliminate them ASAP to keep that chain intact.
Jump over to the next box and have a conversation with Hermes. After that climb the chain to end the Act.