Changeling Wayfinder
That's already a draw engine in itself, but Tamiyo, Seasoned Scholar pushes it further by nerfing creature attacks and rebuying instants and sorceries from your graveyard
However, as one-off cards that you're hoping will save you for a turn at some point, you can usually do better than generic fog effects
Mirko, Obsessive Theorist Mirko also lets you cheat on the cost of spells, but instead of instants, its creatures, and instead of blindly milling yourself, you get to surveil cards into your graveyard
The most striking thing about it is the clever use of blurred white to simulate fog, in order to mask much of the background and create that trademark sense of Innistrad unease
It's a key part of keeping players with the game long term