Chronic Flooding

Enchant land
Whenever enchanted land becomes tapped, its controller mills three cards.

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Essence Backlash

Counter target creature spell. Essence Backlash deals damage equal to that spell's power to its controller.

Blustersquall

Tap target creature you don't control.
Overload {3}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Lobber Crew

Defender
{T}: This creature deals 1 damage to each opponent.
Whenever you cast a multicolored spell, untap this creature.

Doorkeeper

Defender
{2}{U}, {T}: Target player mills X cards, where X is the number of creatures you control with defender.

Sphinx of the Chimes

Flying
Discard two nonland cards with the same name: Draw four cards.

Island

Pursuit of Flight

Enchant creature
Enchanted creature gets +2/+2 and has "{U}: This creature gains flying until end of turn."

Hover Barrier

Mizzium Mortars

Mizzium Mortars deals 4 damage to target creature you don't control.
Overload {3}{R}{R}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Goblin Electromancer

Instant and sorcery spells you cast cost {1} less to cast.

Mountain

Crosstown Courier

Whenever this creature deals combat damage to a player, that player mills that many cards.