Dreadwaters

Target player mills X cards, where X is the number of lands you control.

Crosstown Courier

Whenever this creature deals combat damage to a player, that player mills that many cards.

Counter target spell unless its controller pays {2}.

Target player mills five cards.
Cycling {U} ({U}, Discard this card: Draw a card.)

Target player mills two cards.
Draw a card.

Enchant player
At the beginning of enchanted player's upkeep, that player mills two cards.

Target player mills three cards.
Flashback {1}{U} (You may cast this card from your graveyard for its flashback cost. Then exile it.)