Flickering Ward

Enchant creature
As Flickering Ward enters, choose a color.
Enchanted creature has protection from the chosen color. This effect doesn't remove Flickering Ward.
{W}: Return Flickering Ward to its owner's hand.

Wrenn and Realmbreaker

Lands you control have "{T}: Add one mana of any color."
+1: Up to one target land you control becomes a 3/3 Elemental creature with vigilance, hexproof, and haste until your next turn. It's still a land.
−2: Mill three cards. You may put a permanent card from among the milled cards into your hand.
−7: You get an emblem with "You may play lands and cast permanent spells from your graveyard."

Venerated Rotpriest

Toxic 1 (Players dealt combat damage by this creature also get a poison counter.)
Whenever a creature you control becomes the target of a spell, target opponent gets a poison counter.

Rocco, Cabaretti Caterer

When Rocco, Cabaretti Caterer enters, if you cast it, you may search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Conviction

Enchant creature
Enchanted creature gets +1/+3.
{W}: Return Conviction to its owner's hand.

Whip Silk

Enchant creature
Enchanted creature has reach. (It can block creatures with flying.)
{G}: Return Whip Silk to its owner's hand.

Cage of Hands

Enchant creature
Enchanted creature can't attack or block.
{1}{W}: Return Cage of Hands to its owner's hand.

Crown of Flames

Enchant creature
{R}: Enchanted creature gets +1/+0 until end of turn.
{R}: Return Crown of Flames to its owner's hand.