Gorgon Upgrade Process
The Gorgon Upgrade process is done through a NPC outside of the wave area. These require different things at each stages. I will give a run down of them here. With the Items needed at each stage.
Alaina Bonnie Knight created a nice Guide here: Gorgon Armor Upgrade.
I recommend you check it out.
Above you will see the process from left to right of Change in look of the upgrades. Yes Gorgon Amour changes as you upgrade it.
So now onto the actual process.