Interdict

Counter target activated ability from an artifact, creature, enchantment, or land. That permanent's activated abilities can't be activated this turn. (Mana abilities can't be targeted.)
Draw a card.

Riptide Replicator

As Riptide Replicator enters, choose a color and a creature type.
Riptide Replicator enters with X charge counters on it.
{4}, {T}: Create an X/X creature token of the chosen color and type, where X is the number of charge counters on Riptide Replicator.

Change of Heart

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Target creature can't attack this turn.

Slivdrazi Monstrosity

Eldrazi you control are Slivers in addition to their other types.
Slivers you control have devoid and annihilator 1.
{3}: Create a 1/1 colorless Eldrazi Sliver creature token. It has "Sacrifice this creature: Add {C}."

Sliv-Mizzet, Hivemind

Slivers you control have flying and "Whenever you draw a card, this creature deals 1 damage to any target" and "{T}: Draw a card."

Banding Sliver

All Slivers have banding. (Any creatures with banding, and up to one without, can attack in a band. Bands are blocked as a group. If any creatures with banding you control are blocking or being blocked by a creature, you divide that creature's combat damage, not its controller, among any of the creatures it's being blocked by or is blocking.)

Metamorphose

Put target permanent an opponent controls on top of its owner's library. That opponent may put an artifact, creature, enchantment, or land card from their hand onto the battlefield.

Riptide Survivor

Morph {1}{U}{U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)
When Riptide Survivor is turned face up, discard two cards, then draw three cards.

Stabilizer

Volrath's Motion Sensor

Enchant player
As Volrath's Motion Sensor enters, choose one of enchanted player's hands. That player balances Volrath's Motion Sensor on the back of that hand.
When Volrath's Motion Sensor falls off the chosen hand, sacrifice Volrath's Motion Sensor and enchanted player loses 3 life.

Sphere of Resistance

Warped Researcher

Whenever a player cycles a card, Warped Researcher gains flying and shroud until end of turn. (It can't be the target of spells or abilities.)