Vertigo Spawn

Defender
Whenever Vertigo Spawn blocks a creature, tap that creature. That creature doesn't untap during its controller's next untap step.

Lofty Denial

Counter target spell unless its controller pays {1}. If you control a creature with flying, counter that spell unless its controller pays {4} instead.

Krovikan Mist

Flying
Krovikan Mist's power and toughness are each equal to the number of Illusions on the battlefield.

Phantasmal Dragon

Flying
When Phantasmal Dragon becomes the target of a spell or ability, sacrifice it.

Phantom Monster

Mesmerizing Benthid

When Mesmerizing Benthid enters, create two 0/2 blue Illusion creature tokens with "Whenever this creature blocks a creature, that creature doesn't untap during its controller's next untap step."
Mesmerizing Benthid has hexproof as long as you control an Illusion.

Phantasmal Bear

When Phantasmal Bear becomes the target of a spell or ability, sacrifice it.

Illusionary Armor

Enchant creature
Enchanted creature gets +4/+4.
When enchanted creature becomes the target of a spell or ability, sacrifice Illusionary Armor.

Thriving Isle

Thriving Isle enters tapped. As it enters, choose a color other than blue.
{T}: Add {U} or one mana of the chosen color.

Phantasmal Form

Until end of turn, up to two target creatures each have base power and toughness 3/3, gain flying, and become blue Illusions in addition to their other colors and types.
Draw a card.

Illusory Ambusher

Flash (You may cast this spell any time you could cast an instant.)
Whenever Illusory Ambusher is dealt damage, draw that many cards.

Lord of the Unreal

Illusion creatures you control get +1/+1 and have hexproof. (They can't be the targets of spells or abilities your opponents control.)