Eidolon of Countless Battles

Bestow {2}{W}{W} (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.)
Eidolon of Countless Battles and enchanted creature each get +1/+1 for each creature you control and +1/+1 for each Aura you control.

Aura Shards

Whenever a creature you control enters, you may destroy target artifact or enchantment.

Cryptolith Rite

Creatures you control have "{T}: Add one mana of any color."

Canopy Cover

Enchant creature
Enchanted creature can't be blocked except by creatures with flying or reach.
Enchanted creature can't be the target of spells or abilities your opponents control.

Darksteel Mutation

Enchant creature
Enchanted creature is an Insect artifact creature with base power and toughness 0/1 and has indestructible, and it loses all other abilities, card types, and creature types.

Alpha Authority

Enchant creature
Enchanted creature has hexproof and can't be blocked by more than one creature.

Shield of the Oversoul

Enchant creature
As long as enchanted creature is green, it gets +1/+1 and has indestructible. (Damage and effects that say "destroy" don't destroy it. If its toughness is 0 or less, it's still put into its owner's graveyard.)
As long as enchanted creature is white, it gets +1/+1 and has flying.

Silence

Your opponents can't cast spells this turn.

Nature's Claim

Destroy target artifact or enchantment. Its controller gains 4 life.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Grand Abolisher

During your turn, your opponents can't cast spells or activate abilities of artifacts, creatures, or enchantments.

Siona, Captain of the Pyleas

When Siona, Captain of the Pyleas enters, look at the top seven cards of your library. You may reveal an Aura card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Whenever an Aura you control becomes attached to a creature you control, create a 1/1 white Human Soldier creature token.

Sterling Grove

Other enchantments you control have shroud. (They can't be the targets of spells or abilities.)
{1}, Sacrifice Sterling Grove: Search your library for an enchantment card, reveal it, then shuffle and put that card on top.

Earthcraft

Tap an untapped creature you control: Untap target basic land.

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Femeref Enchantress

Whenever an enchantment is put into a graveyard from the battlefield, draw a card.

Eidolon of Blossoms

Constellation — Whenever Eidolon of Blossoms or another enchantment you control enters, draw a card.