Examine the lightning pot to obtain the Lightning of Zeus. This ability will allow you to electrocute your enemies and will make them yield blue orbs. Defeat all enemies in the area to open the gate and proceed.
Once the area is clear and the gate is opened, make your way to the top and instead of proceeding forth, jump to the lower left to access the chest containing the fifth Phoenix Feather and two red Chests.
Head to the main path and open the red chest below. Don't go down the ramp yet. Instead, run to the opposite direction and follow the path until you find a Gorgon Eye and a red chest.
Now make your way back to the ramp and slide down. Jump across then immediately grapple the glowing green object to tether yourself on the wall. Continue climbing and scaling the broken pieces of the mechanical snake until you reach the point where you need to jump off the hole and swing to the next python. There, you have to smash the side to enter it and slide down the icy interior until make it outside.
Once outside, destroy the eggs and kill any hatchlings that will come out. Scale the wall again until you reach the top then pull the metal ring holding the red python in place. Once it starts to move, wait until you get the prompt to jump to the next python. There you'll be attacked by a manticore. Complete the QTE sequence and you'll be on the purple python.
Destroy the eggs and enemies along the way then slide down again. Jump across and climb up the wall. Follow the straightforward path then swing to the ice wall ahead. Kill the enemies there and open the health and magic Chests as necessary.
Tether again to the next python and pull the ring apart to free the purple python.