Brine Seer

{2}{U}, {T}: Reveal any number of blue cards in your hand. Counter target spell unless its controller pays {1} for each card revealed this way.

Stitcher Geralf

{2}{U}, {T}: Each player mills three cards. Exile up to two creature cards put into graveyards this way. Create an X/X blue Zombie creature token, where X is the total power of the cards exiled this way.

Steel Hellkite

Flying
{2}: This creature gets +1/+0 until end of turn.
{X}: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by this creature this turn. Activate only once each turn.

Rex, Cyber-Hound

Whenever Rex deals combat damage to a player, they mill two cards and you get {E}{E} (two energy counters).
Pay {E}{E}: Choose target creature card in a graveyard. Exile it with a brain counter on it. Activate only as a sorcery.
Rex has all activated abilities of all cards in exile with brain counters on them.

Dulcet Sirens

{U}, {T}: Target creature attacks target opponent this turn if able.
Morph {U} (You may cast this card face down as a 2/2 creature for {3}. Turn it face up any time for its morph cost.)

Sailmonger

{2}: Target creature gains flying until end of turn. Any player may activate this ability.

Steam Catapult

{T}: Destroy target tapped creature. Activate only during your turn, before attackers are declared.

Homarid Warrior

{U}: This creature gains shroud until end of turn and doesn't untap during your next untap step. Tap it. (A creature with shroud can't be the target of spells or abilities.)

Kozilek, the Great Distortion

When you cast this spell, if you have fewer than seven cards in hand, draw cards equal to the difference.
Menace
Discard a card with mana value X: Counter target spell with mana value X.

Pili-Pala

Flying
{2}, {Q}: Add one mana of any color. ({Q} is the untap symbol.)

Horseshoe Crab

Silver Wyvern

Flying
{U}: Change the target of target spell or ability that targets only this creature. The new target must be a creature.

Disruptive Student

{T}: Counter target spell unless its controller pays {1}.

Aboshan, Cephalid Emperor

Tap an untapped Octopus you control: Tap target permanent.
{U}{U}{U}: Tap all creatures without flying.

Sighted-Caste Sorcerer

Exalted (Whenever a creature you control attacks alone, that creature gets +1/+1 until end of turn.)
{U}: This creature gains shroud until end of turn. (It can't be the target of spells or abilities.)

Deathless Angel

Flying
{W}{W}: Target creature gains indestructible until end of turn.

Crovax, Ascendant Hero

Other white creatures get +1/+1.
Nonwhite creatures get -1/-1.
Pay 2 life: Return Crovax to its owner's hand.

Aethergeode Miner

Whenever this creature attacks, you get {E}{E} (two energy counters).
Pay {E}{E}: Exile this creature, then return it to the battlefield under its owner's control.

Lady Sun

{T}: Return Lady Sun and another target creature to their owners' hands. Activate only during your turn, before attackers are declared.

Stonehewer Giant

Vigilance
{1}{W}, {T}: Search your library for an Equipment card, put it onto the battlefield, attach it to a creature you control, then shuffle.

Voltaic Construct

Pale Wayfarer

{2}{W}{W}, {Q}: Target creature gains protection from the color of its controller's choice until end of turn. ({Q} is the untap symbol.)

Escape Artist

This creature can't be blocked.
{U}, Discard a card: Return this creature to its owner's hand.

Cephalid Inkshrouder

Discard a card: This creature gains shroud until end of turn and can't be blocked this turn. (A creature with shroud can't be the target of spells or abilities.)

Mother of Runes

{T}: Target creature you control gains protection from the color of your choice until end of turn.

Wishmonger

{2}: Target creature gains protection from the color of its controller's choice until end of turn. Any player may activate this ability.

Magus of the Disk

This creature enters tapped.
{1}, {T}: Destroy all artifacts, creatures, and enchantments.

Diplomatic Escort

{U}, {T}, Discard a card: Counter target spell or ability that targets a creature.

Darting Merfolk

{U}: Return this creature to its owner's hand.

Vedalken Mastermind

{U}, {T}: Return target permanent you control to its owner's hand.

Riptide Mangler

{1}{U}: Change this creature's base power to target creature's power. (This effect lasts indefinitely.)

Dukhara Peafowl

{U}: This creature gains flying until end of turn.

Jamuraan Lion

{W}, {T}: Target creature can't block this turn.

Amaranthine Wall

Defender
{2}: This creature gains indestructible until end of turn. (Damage and effects that say "destroy" don't destroy it.)

Memnarch

{1}{U}{U}: Target permanent becomes an artifact in addition to its other types. (This effect lasts indefinitely.)
{3}{U}: Gain control of target artifact. (This effect lasts indefinitely.)

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.

Loxodon Lifechanter

When this creature enters, you may have your life total become the total toughness of creatures you control.
{5}{W}: This creature gets +X/+X until end of turn, where X is your life total.

Aetherling

{U}: Exile this creature. Return it to the battlefield under its owner's control at the beginning of the next end step.
{U}: This creature can't be blocked this turn.
{1}: This creature gets +1/-1 until end of turn.
{1}: This creature gets -1/+1 until end of turn.

Jace's Archivist

{U}, {T}: Each player discards their hand, then draws cards equal to the greatest number of cards a player discarded this way.