Misc
The mounted heads of Rocky and Bullwinkle are on the wall. The dartboard is being held up by one of the butler dudes; there is a dart sticking out of his head.
Panel 3: Both the silverware and the pheasants they’re eating are sparkling as if they’ve been plated with gold.
Panel 4: The two of them are now wearing red and black robes and are preparing to sacrifice a butler, who is tied to a stone table. The butler seems surprisingly calm about this. Displayed on a shelf in the background are the decapitated heads of George Washington, Batman, Underdog, Sherlock Holmes, Dick Tracy, Garfield the cat, and the Monopoly Man.
Random Rocky and Bullwinkle
Lol, love how that's the "random" cameo to you, and not Batman, or Garfield.
I find the heads in the sacrifice room to be clear famous characters, while the half hidden trophies in the second panel to be an easier to miss reference.