Dungeon Geists

Flying
When Dungeon Geists enters, tap target creature an opponent controls. That creature doesn't untap during its controller's untap step for as long as you control Dungeon Geists.

Island

Archaeomancer

When Archaeomancer enters, return target instant or sorcery card from your graveyard to your hand.

Befuddle

Target creature gets -4/-0 until end of turn.
Draw a card.

Charmed Sleep

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

Vedalken Mesmerist

Whenever Vedalken Mesmerist attacks, target creature an opponent controls gets -2/-0 until end of turn.

Disperse

Return target nonland permanent to its owner's hand.

Quick Study

Library Larcenist

Whenever Library Larcenist attacks, draw a card.

Cloaked Siren

Flash (You may cast this spell any time you could cast an instant.)
Flying

Cancel

Augury Owl

Flying
When Augury Owl enters, scry 3. (Look at the top three cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Wall of Runes

Defender (This creature can't attack.)
When Wall of Runes enters, scry 1. (Look at the top card of your library. You may put that card on the bottom.)