Ixalan

Deeproot Waters | Enchantment | | Whenever you cast a Merfolk spell, create a 1/1 blue Merfolk creature token with hexproof. (A creature with hexproof can't be the target of spells or abilities your opponents control.) | Zezhou Chen

Navigator's Ruin | Enchantment | | Raid — At the beginning of your end step, if you attacked this turn, target opponent mills four cards. | Zoltan Boros