Hidden Ancients

When an opponent casts an enchantment spell, if this permanent is an enchantment, it becomes a 5/5 Treefolk creature.

Replenish

Return all enchantment cards from your graveyard to the battlefield. (Auras with nothing to enchant remain in your graveyard.)

Plains

Opal Gargoyle

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 2/2 Gargoyle creature with flying.

Brawn

Trample
As long as this card is in your graveyard and you control a Forest, creatures you control have trample.

Hidden Predators

When an opponent controls a creature with power 4 or greater, if this permanent is an enchantment, it becomes a 4/4 Beast creature.

Forest

Opal Champion

When an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 3/3 Knight creature with first strike.

Hidden Stag

Whenever an opponent plays a land, if this permanent is an enchantment, it becomes a 3/2 Elk Beast creature.
Whenever you play a land, if this permanent is a creature, it becomes an enchantment.

Valor

First strike
As long as this card is in your graveyard and you control a Plains, creatures you control have first strike.

Hidden Guerrillas

When an opponent casts an artifact spell, if this permanent is an enchantment, it becomes a 5/3 Soldier creature with trample.

Seal of Cleansing

Sacrifice this enchantment: Destroy target artifact or enchantment.

Hidden Spider

When an opponent casts a creature spell with flying, if this permanent is an enchantment, it becomes a 3/5 Spider creature with reach. (It can block creatures with flying.)

Fecundity

Whenever a creature dies, that creature's controller may draw a card.

Opal Acrolith

Whenever an opponent casts a creature spell, if this permanent is an enchantment, it becomes a 2/4 Soldier creature.
{0}: This permanent becomes an enchantment.

Overrun

Creatures you control get +3/+3 and gain trample until end of turn. (Each of those creatures can deal excess combat damage to the player or planeswalker it's attacking.)

Hidden Gibbons

When an opponent casts an instant spell, if this permanent is an enchantment, it becomes a 4/4 Ape creature.

Hidden Herd

When an opponent plays a nonbasic land, if this permanent is an enchantment, it becomes a 3/3 Beast creature.