Cauldron's Gift: A five CMC reanimation spell is usually barely passable in limited -
Rescue from the Underworld was an exception due to being instant-speed and possibly a 2-for-1. So I don't have high hopes for this one.
Forever Young: Interesting - it's one CMC cheaper than
Footbottom Feast and
Bone Harvest but also sorcery speed. Given the effect, I think I'm 100% in to pay one less mana and be forced to do this on my turn, Still probably casual/limited only but seems good, and seems especially bonkers in a limited with Adventures.
The Cauldron of Eternity: Any self-respecting deck should be capable of casting this for BB. The problem is whether or not it's "good enough" even at
BB to cast and
2B to activate - that's still effectively five mana and two life at sorcery speed for your first dude, which reminds me too much of
Strands of Night and
Chainer, Dementia Master. It'll depend a lot on just how many powerful targets we have - since
Whip of Erebos did see some play in its heyday.