>>96399013
He's better in the 99 anyway. I have him in my Zur deck and I don't think I've ever cast him for more than X = 2, so his self-mill is a bit pathetic. The escape cost is pretty steep too, but it's worth it once in a while to support a different strategy, I think for building around it's just not good enough value. Especially because you will dedicate a lot of cards in the 99 to self-milling, which will compete with your slots for enchantments.
Him suddenly being hexproof, lifelink, deathtouch from Zur goes so hard.

I would recommend either Ghen Arcanum Weaver or Bruna Light of Alabaster. Neither are in exactly esper colors, but they are more effective.

Ghen's ability is a much better cost and because nothing is exiled, you can basically keep going round and round if your grave isn't stacked. I also think red enchants can be underrated and having access to them is pretty good.

Bruna recovers all auras in your grave AND everything on the whole field (including opponents) AND in your hand. You won't feel as bad about dedicating slots to self-mill because recovering all auras in grave is just nutty value. She does get a bit kill-on-sight once people are wise to how she works, and having to attack or defend to move auras rather than just putting it on an ETB is a little rough, but you're in the best colors for recovery.

>>96309158
I have never found a deck that benefits from running this. Without fail 10 mana is just too late game. By the time it comes down you've already played something like 90% of all the cards you were ever likely to play in the game to begin with.

My copy has bounced around 3 or 4 different decks, but I now have it in Zur Eternal Schemer because if it comes out it can be a 10/10 beater, and there's like 5 or more cards in the deck that would reduce the cost to cast it so it'll end up closer to 7 than 10, but still.