Containment Priest

Flash
If a nontoken creature would enter and it wasn't cast, exile it instead.

Smirking Spelljacker

Flash
Flying
When Smirking Spelljacker enters, exile target spell an opponent controls.
Whenever Smirking Spelljacker attacks, if a card is exiled with it, you may cast the exiled card without paying its mana cost.

Angel of Grace

Flash
Flying
When Angel of Grace enters, until end of turn, damage that would reduce your life total to less than 1 reduces it to 1 instead.
{4}{W}{W}, Exile Angel of Grace from your graveyard: Your life total becomes 10.

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.

Gerrard's Hourglass Pendant

Flash
If a player would begin an extra turn, that player skips that turn instead.
{4}, {T}, Exile Gerrard's Hourglass Pendant: Return to the battlefield tapped all artifact, creature, enchantment, and land cards in your graveyard that were put there from the battlefield this turn.

Spectral Sailor

Flash (You may cast this spell any time you could cast an instant.)
Flying
{3}{U}: Draw a card.

Faerie Mastermind

Flash
Flying
Whenever an opponent draws their second card each turn, you draw a card.
{3}{U}: Each player draws a card.

Hushwing Gryff

Flash
Flying
Creatures entering don't cause abilities to trigger.

Frilled Mystic

Flash
When Frilled Mystic enters, you may counter target spell.

Mystic Snake

Flash
When Mystic Snake enters, counter target spell.

Cathar Commando

Flash (You may cast this spell any time you could cast an instant.)
{1}, Sacrifice this creature: Destroy target artifact or enchantment.

Caller of the Claw

Flash
When Caller of the Claw enters, create a 2/2 green Bear creature token for each nontoken creature put into your graveyard from the battlefield this turn.

Wreck Hunter

Flash
When Wreck Hunter enters, choose target player. You create a tapped Powerstone token for each nonland card in that player's graveyard that was put there from the battlefield this turn. (It's an artifact with "{T}: Add {C}. This mana can't be spent to cast a nonartifact spell.")

Venser, Shaper Savant

Flash (You may cast this spell any time you could cast an instant.)
When Venser, Shaper Savant enters, return target spell or permanent to its owner's hand.

Naru Meha, Master Wizard

Flash
When Naru Meha, Master Wizard enters, copy target instant or sorcery spell you control. You may choose new targets for the copy.
Other Wizards you control get +1/+1.

Crafty Cutpurse

Flash
When Crafty Cutpurse enters, each token that would be created under an opponent's control this turn is created under your control instead.

Cunning Nightbonder

Flash
Spells with flash you cast cost {1} less to cast and can't be countered.

Deputy of Acquittals

Flash (You may cast this spell any time you could cast an instant.)
When Deputy of Acquittals enters, you may return another target creature you control to its owner's hand.

Kyodai, Soul of Kamigawa

Flash
Flying
When Kyodai, Soul of Kamigawa enters, another target permanent gains indestructible for as long as you control Kyodai.
{W}{U}{B}{R}{G}: Kyodai gets +5/+5 until end of turn.

Samwise the Stouthearted

Flash
When Samwise the Stouthearted enters, choose up to one target permanent card in your graveyard that was put there from the battlefield this turn. Return it to your hand. Then the Ring tempts you.

Archivist of Oghma

Flash
Whenever an opponent searches their library, you gain 1 life and draw a card.

Doorkeeper Thrull

Flash
Flying
Artifacts and creatures entering don't cause abilities to trigger.

Garna, the Bloodflame

Flash
When Garna, the Bloodflame enters, return to your hand all creature cards in your graveyard that were put there from anywhere this turn.
Other creatures you control have haste.

Lobelia Sackville-Baggins

Flash
Menace
When Lobelia Sackville-Baggins enters, exile target creature card from an opponent's graveyard that was put there from the battlefield this turn, then create X Treasure tokens, where X is the exiled card's power.

Deep Gnome Terramancer

Flash
Mold Earth — Whenever one or more lands enter under an opponent's control without being played, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle. Do this only once each turn.

Errant and Giada

Flash
Flying
You may look at the top card of your library any time.
You may cast spells with flash or flying from the top of your library.

Slitherwisp

Flash
Whenever you cast another spell that has flash, you draw a card and each opponent loses 1 life.