Necroduality

Enchantment

Whenever a nontoken Zombie enters the battlefield under your control, create a token that's a copy of that creature.

Nyxborn Seaguard

Enchantment Creature — Merfolk Soldier (2/5)

Octopus Umbra

Enchantment — Aura

Enchant creature
Enchanted creature has base power and toughness 8/8 and has "Whenever this creature attacks, you may tap target creature with power 8 or less."
Totem armor (If enchanted creature would be destroyed, instead remove all damage from it and destroy this Aura.)

Ocular Halo

Enchantment — Aura

Enchant creature
Enchanted creature has ": Draw a card."
: Enchanted creature gains vigilance until end of turn.

One with the Stars

Enchantment — Aura

Enchant creature or enchantment
Enchanted permanent is an enchantment and loses all other card types. (It still has its abilities, but it's no longer a creature.)

Opposition

Enchantment

Tap an untapped creature you control: Tap target artifact, creature, or land.

Perplexing Chimera

Enchantment Creature — Chimera (3/3)

Whenever an opponent casts a spell, you may exchange control of Perplexing Chimera and that spell. If you do, you may choose new targets for the spell. (If the spell becomes a permanent, you control that permanent.)

Persuasion

Enchantment — Aura

Enchant creature (Target a creature as you cast this. This card enters the battlefield attached to that creature.)
You control enchanted creature.

Protective Bubble

Enchantment — Aura

Enchant creature
Enchanted creature can't be blocked and has shroud. (It can't be the target of spells or abilities.)

Psychic Possession

Enchantment — Aura

Enchant opponent
Skip your draw step.
Whenever enchanted opponent draws a card, you may draw a card.

Reconnaissance Mission

Enchantment

Whenever a creature you control deals combat damage to a player, you may draw a card.
Cycling (, Discard this card: Draw a card.)

Reflections of Littjara

Enchantment

As Reflections of Littjara enters the battlefield, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Rooftop Storm

Enchantment

You may pay rather than pay the mana cost for Zombie creature spells you cast.

Serpent of Yawning Depths

Enchantment Creature — Serpent (6/6)

Krakens, Leviathans, Octopuses, and Serpents you control can't be blocked except by Krakens, Leviathans, Octopuses, and Serpents.

Shark Typhoon

Enchantment

Whenever you cast a noncreature spell, create an X/X blue Shark creature token with flying, where X is that spell's mana value.
Cycling (, Discard this card: Draw a card.)
When you cycle Shark Typhoon, create an X/X blue Shark creature token with flying.

Shimmer

Enchantment

As Shimmer enters the battlefield, choose a land type.
Each land of the chosen type has phasing. (It phases in or out before its controller untaps during each of their untap steps. While it's phased out, it's treated as though it doesn't exist.)

Skywise Teachings

Enchantment

Whenever you cast a noncreature spell, you may pay . If you do, create a 2/2 blue Djinn Monk creature token with flying.

Sleep Paralysis

Enchantment — Aura

Enchant creature
When Sleep Paralysis enters the battlefield, tap enchanted creature.
Enchanted creature doesn't untap during its controller's untap step.

Sleep with the Fishes

Enchantment — Aura

Enchant creature
When Sleep with the Fishes enters the battlefield, tap enchanted creature and you create a 1/1 blue Fish creature token with "This creature can't be blocked."
Enchanted creature doesn't untap during its controller's untap step.

Song of Creation

Enchantment

You may play an additional land on each of your turns.
Whenever you cast a spell, draw two cards.
At the beginning of your end step, discard your hand.