Gorgon Eyes/Phoenix Feathers/Minotaur Horns (Ghost of Sparta)
There are more than enough of these in the game, so if you miss any of the chests in the video, then there will be extra chests later in the game with them in it. If you have collected 15 of any of the collectibles, then any chests later in the game with them in it will yield red orbs instead.