Crystalline Nautilus

Bestow {3}{U}{U} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
When this permanent becomes the target of a spell or ability, sacrifice it.
Enchanted creature gets +4/+4 and has "When this creature becomes the target of a spell or ability, sacrifice it."

Porphyry Nodes

At the beginning of your upkeep, destroy the creature with the least power. It can't be regenerated. If two or more creatures are tied for least power, you choose one of them.
When there are no creatures on the battlefield, sacrifice this enchantment.

Coral Net

Enchant green or white creature
Enchanted creature has "At the beginning of your upkeep, sacrifice this creature unless you discard a card."

Candletrap

Enchant creature
Enchanted creature has defender.
Prevent all combat damage that would be dealt by enchanted creature.
Coven — {2}{W}, Sacrifice this Aura: Exile enchanted creature. Activate only if you control three or more creatures with different powers.

Tameshi, Reality Architect

Whenever one or more noncreature permanents are returned to hand, draw a card. This ability triggers only once each turn.
{X}{W}, Return a land you control to its owner's hand: Return target artifact or enchantment card with mana value X or less from your graveyard to the battlefield. Activate only as a sorcery.

Mind Harness

Enchant red or green creature
Cumulative upkeep {1} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
You control enchanted creature.

Essence Leak

Enchant permanent
As long as enchanted permanent is red or green, it has "At the beginning of your upkeep, sacrifice this permanent unless you pay its mana cost."

Dawn Evangel

Whenever a creature dies, if an Aura you controlled was attached to it, return target creature card with mana value 2 or less from your graveyard to your hand.

Dispeller's Capsule

{2}{W}, {T}, Sacrifice this artifact: Destroy target artifact or enchantment.

Eidolon of Philosophy

{6}{U}, Sacrifice this creature: Draw three cards.

Soul Snare

{W}, Sacrifice this enchantment: Exile target creature that's attacking you or a planeswalker you control.

Mana Chains

Enchant creature
Enchanted creature has "Cumulative upkeep {1}." (At the beginning of its controller's upkeep, that player puts an age counter on it, then sacrifices it unless they pay its upkeep cost for each age counter on it.)

Aegis of the Gods

You have hexproof. (You can't be the target of spells or abilities your opponents control.)

Seal of Removal

Sacrifice this enchantment: Return target creature to its owner's hand.

Alseid of Life's Bounty

Lifelink
{1}, Sacrifice this creature: Target creature or enchantment you control gains protection from the color of your choice until end of turn.