Wall of Lost Thoughts

Defender (This creature can't attack.)
When Wall of Lost Thoughts enters, target player mills four cards. (They put the top four cards of their library into their graveyard.)

Snapping Drake

Flying (This creature can't be blocked except by creatures with flying or reach.)

Island

Dampening Pulse

Creatures your opponents control get -1/-0.

Aether Tunnel

Enchant creature
Enchanted creature gets +1/+0 and can't be blocked.

Quick Study

Witching Well

When Witching Well enters, scry 2. (Look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)
{3}{U}, Sacrifice Witching Well: Draw two cards.

Cold-Water Snapper

Hexproof (This creature can't be the target of spells or abilities your opponents control.)

Mind Sculpt

Tolarian Scholar

Unsummon

Return target creature to its owner's hand.

Cancel

Flood of Tears

Return all nonland permanents to their owners' hands. If you return four or more nontoken permanents you control this way, you may put a permanent card from your hand onto the battlefield.