What happens if the Glutton Cauldron is sacrificed or returned to hand? Do the energy tokens on it return to the player's reserve, or are they lost?
My instincts from other games would suggest they're discarded, but since the energy on the Cauldron would eventually be returned to the player's reserve, and the card is so weak anyway, a shadow of doubt crept into my mind. And so I'm asking here.
Cauldron is consumed and gone. I agree; it's not a fabulous card but I like it in some ways. It's a side mini-quest; to just stow energy for year 3 and gain 15 crystals for your trouble and to free up its gauge spot later. This cauldron works wonders if you have the Potion of Life and the Grimoire set up, plus Purse of Io on top of the Potion of Life. BUT.....Cauldron is hard-counter drafted by Thieving Faeries and it hurts you a little if you're looking for Ragfield's Helm to trigger (like any other consuming item).
My advice is not to pick cauldron early and check the draft packs for a Thieving Faeries first; it's a full 21 point swing plus a crippling effect if your lingering around 0 crystals.