While not quite a proper mana doubler, its still a whole pile of extra mana when considering the cards low cost
Red Cheeks copies typically command a 20 to 50% premium over Yellow Cheeks at the same grade
In other words, while the payoff here is great, it's expensive at eight energy for a 6/6, and it's unlikely to help pay for much of that
Additionally, all of the play mats, dice, and condition markers will have a gold covering on them
Dark Ritual allows you to take advantage of drawing multiple cards a turn back during the black summer of Magic , it wasn't unusual to see a player drawing 4-5 cards a turn every turn of the game using Necropotence to fuel their crazed game of "holy cow, is this for real?" No other card in Magic has allowed a player to draw so many cards turn after turn so cheaply