Teferi's Tutelage

Mill decks have always faced the same structural problem: the effect is passive, it doesn't affect the board, and every card spent grinding a library is a card not spent staying alive. This enchantment answers that by welding the mill trigger onto something a blue deck was going to do anyway. Every draw the deck makes becomes two cards off the opponent's library, so cantrips, card-advantage engines, and end-step draw spells all shed incidental mill without the deck committing slots to dedicated grind spells. That coupling is the whole design idea: it converts a shell built to survive and dig into one that closes through the top of the opposing deck as a byproduct of its normal operation. The entry loot is not just a smoothing effect; that draw triggers the enchantment's own mill clause the turn it lands, so the card mills two on the way in and does something against decks light on early pressure. The catch is that it produces nothing on its own: the trigger is entirely parasitic on how often you draw, and against a deck that stops you drawing, it sits inert. Multiple copies stack cleanly rather than compounding, since each one watches the same draws independently: a second copy turns every draw into four mill instead of two, but neither copy generates draws for the other. The reward scales with the draw engine you bring, not with the enchantment itself.