So, here's my progress with the objects/characters I'll be using in sketch 2 so far. I'll be trying to create a Mount Olympus set and an Underworld set.
These are a bunch of skulls and bones that I want to have scattered around the background of the Underworld.
This is all I have for Hades right now. I based the helmet and the fork thing on objects that Hades apparently used in Greek mythology (according to some brief research that I did).