Leeching Sliver

Whenever a Sliver you control attacks, defending player loses 1 life.

Telekinetic Sliver

All Slivers have "{T}: Tap target permanent."

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Syphon Sliver

Sliver creatures you control have lifelink. (Damage dealt by a Sliver creature you control also causes you to gain that much life.)

Force of Negation

If it's not your turn, you may exile a blue card from your hand rather than pay this spell's mana cost.
Counter target noncreature spell. If that spell is countered this way, exile it instead of putting it into its owner's graveyard.

Dismember

({B/P} can be paid with either {B} or 2 life.)
Target creature gets -5/-5 until end of turn.

Wasteland

{T}: Add {C}.
{T}, Sacrifice Wasteland: Destroy target nonbasic land.

Leyline of the Void

If Leyline of the Void is in your opening hand, you may begin the game with it on the battlefield.
If a card would be put into an opponent's graveyard from anywhere, exile it instead.

Secluded Courtyard

As this land enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Muscle Sliver

Sliver Hive

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a Sliver spell.
{5}, {T}: Create a 1/1 colorless Sliver creature token. Activate only if you control a Sliver.

Homing Sliver

Each Sliver card in each player's hand has slivercycling {3}.
Slivercycling {3} ({3}, Discard this card: Search your library for a Sliver card, reveal it, put it into your hand, then shuffle.)

Pithing Needle

As Pithing Needle enters, choose a card name.
Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

Karakas

{T}: Add {W}.
{T}: Return target legendary creature to its owner's hand.

Plague Engineer

Deathtouch
As Plague Engineer enters, choose a creature type.
Creatures of the chosen type your opponents control get -1/-1.

Hibernation Sliver

All Slivers have "Pay 2 life: Return this permanent to its owner's hand."

Sinew Sliver

Harmonic Sliver

All Slivers have "When this permanent enters, destroy target artifact or enchantment."

Cavern of Souls

As Cavern of Souls enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type, and that spell can't be countered.

Predatory Sliver

Unclaimed Territory

As Unclaimed Territory enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type.

Mutavault

{T}: Add {C}.
{1}: Mutavault becomes a 2/2 creature with all creature types until end of turn. It's still a land.

Galerider Sliver

Sliver creatures you control have flying.

Striking Sliver

Sliver creatures you control have first strike. (They deal combat damage before creatures without first strike.)

Aether Vial

At the beginning of your upkeep, you may put a charge counter on Aether Vial.
{T}: You may put a creature card with mana value equal to the number of charge counters on Aether Vial from your hand onto the battlefield.

Venom Sliver

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Force of Will

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost.
Counter target spell.