Drowner Initiate

Whenever you cast a blue spell, target player mills two cards.

Whenever you cast a historic spell, target player mills two cards. (Artifacts, legendaries, and Sagas are historic.)

, : Target player mills two cards.

Constellation — Whenever an enchantment you control enters, target player mills two cards.

Whenever this creature deals damage, target player mills that many cards.

Whenever you draw a card, you may have target player mill a card.