Wizards attempted to create a “fairer” version of Fact or Fiction with Steam Augury in Theros. It cost 4 mana, too, but required a Red mana in addition to a Blue. Functionally, it was about the same card. But it only saw fringe Standard play, and shows up occasionally in some Grixis (red/blue/black) control decks in Modern.
Today, Fact or Fiction still sees play in some Legacy decks. Some Miracles, Omni-Tell, and Esper Mentor decks have played a copy, sometimes in the sideboard. But mostly, both it and Steam Augury have become Commander only cards. Well, Wizards decided to print another Fact or Fiction variant, more in the vein of Steam Augury. But this time, it scales to how much mana you pump into it.
So in many people’s view, Epiphany at the Drownyard, then, will often give you “bad” cards. In some graveyard based decks, this isn’t really a problem, though. Also, if you get certain combinations of cards, the pile chosen may not matter
Beyond this, the only difference is that it costs X. Interestingly, it allows you to pick up the top X + 1 cards instead of the 5 that both Fact or Fiction and Steam Augury gave you. This means you’d have to make X equal 4 to get the same value. In a graveyard-based environment, though, paying 3 for X and 4 cards may be fine. What makes this card special is that you can put as much as you want into it. The more you get to choose, the more dangerous it becomes.
On the surface, this seems strictly worse. But the tradeoff comes in how much you choose to put into it. You could pay only 2 mana for this (1 and a Blue) and reveal only 2 cards. You could put 10 mana into it and reveal 11. Decks that want to put cards in the graveyard have to love this card. If decks built around Delirium ever take off, you’re probably going to want this. It’s tricky to get 4 different card types into the graveyard, but not if you have this around.
I really like this card in a midrange control deck where you can afford to lose some cards in order to gain some. What made Fact or Fiction so good, though, is that you could count on 5 cards every time. The variance of this card could either make it super good or super bad. An opponent could just choose to make you lose every card you reveal - a pile can be zero cards, by the way. So you have to be careful. Also, you don’t actually discard the cards that go to the graveyard, so it doesn’t trigger Madness.
If this had been printed during the original Innistrad when Flashback was around, this would’ve been ridiculously good. There’s a chance it will still be good, though. I can even see a Modern deck or two wanting to include this. If you really don’t care what ends up in your graveyard, it’s perfectly fine. I could see a Dredgevine deck wanting to use this. Getting another way to consistently get to more copies of Bloodghast, Gravecrawler and Vengevine seems good to me - although I think that deck already has the tools it needs. But I can see people toying with it in that case.
It’s also good with one of my favorite Commanders from Khans of Tarkir, Sidisi, Brood Tyrant. Fact or Fiction is a good card in that deck, because it triggers Sidisi’s ability to create a Zombie whenever a creature hits the graveyard from the library. You only get one token no matter how many creatures hit at once, though. But it still works in the deck, plus gives you the chance to fill the graveyard at a much greater clip. I like it there. Actually, there are quite a few Commander decks that may play this over Fact or Fiction, since you can have a billion mana over the course of a game to throw into it.
There are other Zombie decks that could take advantage of Epiphany, too. Grimgrin, Corpse-Born doesn't mind dumping a whole bunch of its deck. Certain builds of Thraximundar Zombie decks don’t mind, either, and those decks tend to have more combo elements that you can dig for. Stitcher Geralf is the Legendary Creature that I hear thrown around a lot in reference to this card, and I see ways it could work.
I’ve always been fond of X spells. Part of their appeal is just how much you can do with them given the proper mana. It’s why cards like Banefire and Epic Experiment have always been so fun to play with - they only get better the more you have to pump into them. Granted Epic Experiment was never the consistent tournament winner that Banefire was, but ask a Commander player what Epic Experiment does with the amazing mana base of Commander. It makes EDH players sad. I don’t see Epiphany at the Drownyard being that level of epic, of course, cause it doesn’t actually win you the game outright. But we live in a world where Laboratory Maniac is a win condition in Modern (yes, really, as an alternate win-con in Ad Nauseum Combo). So running out of cards can actually be a good thing.
This could be a pretty decent card in Standard and I actually see people brewing with it in Modern, and even Legacy. Is it less efficient than Fact or Fiction? Most certainly. But I do like it better than Steam Augury, since this requires only one color of mana. And for Sidisi, Brood Tyrant and the many other graveyard-based EDH decks out there, I’d definitely play it.