Aven Mindcensor

Flash
Flying
If an opponent would search a library, that player searches the top four cards of that library instead.

Mana Tithe

Counter target spell unless its controller pays {1}.

Sulfur Elemental

Flash
Split second (As long as this spell is on the stack, players can't cast spells or activate abilities that aren't mana abilities.)
White creatures get +1/-1.

Stingscourger

Echo {3}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Stingscourger enters, return target creature an opponent controls to its owner's hand.

Stonecloaker

Flash
Flying
When Stonecloaker enters, return a creature you control to its owner's hand.
When Stonecloaker enters, exile target card from a graveyard.

Orcish Cannonade

Orcish Cannonade deals 2 damage to any target and 3 damage to you.
Draw a card.

Simian Spirit Guide

Exile Simian Spirit Guide from your hand: Add {R}.

Blade of the Sixth Pride

Mogg War Marshal

Echo {1}{R} (At the beginning of your upkeep, if this came under your control since the beginning of your last upkeep, sacrifice it unless you pay its echo cost.)
When Mogg War Marshal enters or dies, create a 1/1 red Goblin creature token.

Mountain

Sunlance

Sunlance deals 3 damage to target nonwhite creature.

Mindstab

Target player discards three cards.
Suspend 4—{B} (Rather than cast this card from your hand, you may pay {B} and exile it with four time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)

Brute Force

Target creature gets +3/+3 until end of turn.

Vandalblast

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

Coal Stoker

When Coal Stoker enters, if you cast it from your hand, add {R}{R}{R}.

Judge Unworthy

Choose target attacking or blocking creature. Scry 3, then reveal the top card of your library. Judge Unworthy deals damage equal to that card's mana value to that creature.

Riftmarked Knight

Protection from black; flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)
Suspend 3—{1}{W}{W}
When the last time counter is removed from Riftmarked Knight while it's exiled, create a 2/2 black Knight creature token with flanking, protection from white, and haste.

Benalish Cavalry

Flanking (Whenever a creature without flanking blocks this creature, the blocking creature gets -1/-1 until end of turn.)

Fortify

Choose one —
• Creatures you control get +2/+0 until end of turn.
• Creatures you control get +0/+2 until end of turn.

Seal of Primordium

Sacrifice Seal of Primordium: Destroy target artifact or enchantment.

Corpulent Corpse

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.)
Suspend 5—{B} (Rather than cast this card from your hand, you may pay {B} and exile it with five time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost. It has haste.)

Plains

Restoration Angel

Flash
Flying
When Restoration Angel enters, you may exile target non-Angel creature you control, then return that card to the battlefield under your control.

Cautery Sliver

All Slivers have "{1}, Sacrifice this permanent: This permanent deals 1 damage to any target."
All Slivers have "{1}, Sacrifice this permanent: Prevent the next 1 damage that would be dealt to target player, planeswalker, or Sliver creature this turn."

Amrou Scout

{4}, {T}: Search your library for a Rebel permanent card with mana value 3 or less, put it onto the battlefield, then shuffle.

Epic Experiment

Exile the top X cards of your library. You may cast instant and sorcery spells with mana value X or less from among them without paying their mana costs. Then put all cards exiled this way that weren't cast into your graveyard.