Very cool design, and I love the art, it's trippy, beautiful, will look gorgeous in foil and it has a chimera. I dig chimeras.
As for the card itself... well, it's a bit janky. Obviously if your deck is entirely Enchantment Creatures, that's kind of a costless Birthing Pod, but you can search your non-Enchantment Creatures like Setessan Champion too. If you have two copies, you could sack them to each other to get 5 mana creatures, which is neat.
The "issue" from a power-level standpoint is how you can't abuse it as easily as you can with Birthing Pod or Prime Speaker Vannifar. I love this from a design standpoint, because more often than not Pod and Vannifar just boil down to "how much can I untap this to climb the chain and win the game on the spot?", which isn't exactly riveting gameplay, but it does makes this a lot weaker than the other two. And considering how extremely narrow it is, I'm not sure I can justify playing it over, say, Calix, Destiny's Hand. It's definitely a really fun card and I'll probably be brewing with it myself, but it looks like exactly this, a fun card to brew around and not much more.
I wish this could sac itself to act like a tutor for 5 cmc, but maybe that would have been a little too good?
Yep, probably would. Would be basically a X=5 Green Sun's Zenith for 4 mana without the color restriction. Don't think there would be a reason to play anything else in Standard except 5c Niv-Mizzet Reborn and drop 6/6 Dragons that draws you cards for 4 mana all day.
Treacherous Blessing is indeed nice (yet very fair), Pact is bad though (bad curve, underwhelming effect, better when you give it to your opp, etc...). Sagas are very good too.
The best config on top of my head would be a combo kill involving sacrificing a 3-cmc enchantment creature into a 4-cmc win con. If it's not doable, I guess it may still be stronger than Vannifar, it's faster, but we need strong enchantments. Stars must align.