Counter target spell with mana value X. If that spell is targeting you or a creature you control, you may choose new targets for it instead.

When Research Grant enters, look at the top three cards of your library. Put one into your hand and the rest into your graveyard.
You've cast two or more spells this turn.
You've drawn two or more cards this turn.

Target opponent discards their hand, then draws seven cards. You discard your hand, then exile the top seven cards of that player's library. You may play those cards as long as they remain exiled, and mana of any type can be spent to cast them.

Gain control of target creature until end of turn. Untap that creature. It gains haste until end of turn. If you control another permanent you don't own, it gets +2/+0 until end of turn.

At the beginning of combat on your turn, you may pay {1}. If you do, create a 1/1 red and green Elemental creature token. It gains haste. Sacrifice it at end of combat.

When Resourceful Hireling enters, choose one —
• Create a 0/0 colorless Robot artifact creature token with a +1/+1 counter on it.
• Create a Treasure token.

{T}: Add {C}.
Whenever Resting Place attacks, sacrifice it at end of combat.
Spellcharge 5

Vigilance
{2}{W}: Create a Berry token and attach it to Restless Sloth.

This spell has lifelink as long as you control a creature with lifelink.
Retaliatory Outburst deals 4 damage to target tapped creature.

When Retrofit Paladin enters, tap up to two target creatures with power 3 or less.

Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Exile target card from a graveyard.

Defender
As long as you control a creature with power 4 or greater, Revel Watchguard can attack as though it didn't have defender.

Flying
Drop — When Revenant Benefactor enters, if you didn't cast any creature spells during your last turn, return target creature card from your graveyard to the battlefield.

Return target creature card with mana value 4 or less from your graveyard to the battlefield. It gets +2/+1 and gains trample and haste until end of turn. Sacrifice it at the beginning of the next end step.

Trample
Whenever Revolutionary Throng attacks, if you control another creature with power 4 or greater, it gets +2/+0 until end of turn.

When Revved Robo enters, you may put a +1/+1 counter on it. If you don't, it gets +2/+0 and gains haste until end of turn.

Counter target spell. Untap up to four lands.

Draw a card. If you've amped it up this turn, creatures your opponents control get -1/-0 until end of turn.

When Rib Collector enters, if it wandered, return target creature card from your graveyard to your hand.
Wander—{1}{B}, Sacrifice another creature.

Return any number of creature cards with total mana value less than or equal to twice your devotion to black from your graveyard to the battlefield.

Approval — This spell costs {X} less to cast, where X is the number of colors among permanents you control.
Exile target creature.

Search your library for a basic land card, reveal it, put it into your hand, then shuffle. Scry 1.

When Riotous Rockers enters, it deals 3 damage to up to one target that was dealt damage this turn.

Choose one —
• Exile target artifact or enchantment.
• Exile target creature you control, then return it to the battlefield under its owner's control. If that creature entering the battlefield causes any abilities to trigger, those abilities trigger an additional time.

Search your library for a card with flashback and exile it, then shuffle. You may cast that card this turn. At the beginning of your next end step, if that card is in exile, put it into your graveyard.
Flashback {U}{R}