last edited by Brass Man
I suppose there are two possible approaches.
You can use Replenish as a combo card by building a deck that puts a kill in the yard. I remember Pandemonium+Saproling Burst, though there are probably a lot of other 2 card kills now. I suspect that this runs into the problems @Topical_Island mentioned. I wouldn't say the idea is a total nonstarter though, as I can't think of anything that combo is strictly worse than. There are a few things Replenish has going for it that other cards don't ... I don't know if those things are that important, but I've never tested it to know for sure.
You can use Replenish as a utility card in a deck that already happens to have enchantments that might end up in the graveyard ... either by being destroyed or put there (with an Entomb or a Gifts Ungiven or whatever). This approach is super interesting from a brewing perspective, but I don't know if the power level is there.
Is @hierarchnoble 's Bargain comment the most telling? Is Entomb+Yawgmoth's Bargain the way forward? That feels a little pricey to me, but it's not out of the question.
Vintage Enchantress would run Replenish, but I don't know what Vintage Enchantress is viable.
How about the Academy Rector+Omniscience decks ... possibly worthwhile there? Though Rector is just better, I don't know if you need 8 of that effect ... but it's possible.
How about a Reanimator deck that already runs Entomb and .... Animate Dead. That's some damn cool synergy. No clue if it's any good.
I think I'm actually most interested in the idea of a Landstill deck. There's an absolutely clear path there to getting enchantments in the yard. Replenish to get back 2x Standstill at once is actually pretty mind-boggling. You'd want to combine this with some other enchantments that do something, maybe Oath of Druids or Myth Realized, and make sure to take full advantage of good looting effects like Dack Fayden or Jace, Vryn's Prodigy. Enough of those and you could justify running (a SMALL number of) some of the top end game-ender enchantments, Form of the Dragon or .... Sandwurm Convergence??
okay I think I just talked myself into building a TERRIBLE deck.