Eight-and-a-Half-Tails

{1}{W}: Target permanent you control gains protection from white until end of turn.
{1}: Target spell or permanent becomes white until end of turn.

Hushbringer

Flying, lifelink
Creatures entering or dying don't cause abilities to trigger.

Welcoming Vampire

Flying
Whenever one or more other creatures you control with power 2 or less enter, draw a card. This ability triggers only once each turn.

Aven Mindcensor

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

Glare of Heresy

Circle of Protection: White

{1}: The next time a white source of your choice would deal damage to you this turn, prevent that damage.

Gideon's Defeat

Exile target white creature that's attacking or blocking. If it was a Gideon planeswalker, you gain 5 life.

Mentor of the Meek

Whenever another creature you control with power 2 or less enters, you may pay {1}. If you do, draw a card.

Leonin Arbiter

Players can't search libraries. Any player may pay {2} for that player to ignore this effect until end of turn.

Rune of Protection: White

{W}: The next time a white source of your choice would deal damage to you this turn, prevent that damage.
Cycling {2} ({2}, Discard this card: Draw a card.)

Tomik, Distinguished Advokist

Flying
Lands on the battlefield and land cards in graveyards can't be the targets of spells or abilities your opponents control.
Your opponents can't play land cards from graveyards.

White Knight

First strike (This creature deals combat damage before creatures without first strike.)
Protection from black (This creature can't be blocked, targeted, dealt damage, or enchanted by anything black.)