Gemhide Sliver

All Slivers have "{T}: Add one mana of any color."

The First Sliver

Cascade (When you cast this spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)
Sliver spells you cast have cascade.

Hibernation Sliver

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

Cliffhaven Vampire

Flying
Whenever you gain life, each opponent loses 1 life.

Sliver Overlord

{3}: Search your library for a Sliver card, reveal that card, put it into your hand, then shuffle.
{3}: Gain control of target Sliver. (This effect lasts indefinitely.)

Murasa Pyromancer

Whenever Murasa Pyromancer or another Ally enters the battlefield under your control, you may have Murasa Pyromancer deal damage to target creature equal to the number of Allies you control.

Beastcaller Savant

Haste
{T}: Add one mana of any color. Spend this mana only to cast a creature spell.

Rukarumel, Biologist

As Rukarumel, Biologist enters the battlefield, choose a creature type.
Slivers you control and nontoken creatures you control are the chosen type in addition to their other creature types. The same is true for creature spells you control and creature cards you own that aren't on the battlefield.
{3}, {T}: Create a 1/1 colorless Sliver creature token.

Ondu Cleric

Whenever Ondu Cleric or another Ally enters the battlefield under your control, you may gain life equal to the number of Allies you control.

Sliver Queen

{2}: Create a 1/1 colorless Sliver creature token.

Talus Paladin

Whenever Talus Paladin or another Ally enters the battlefield under your control, you may have Allies you control gain lifelink until end of turn, and you may put a +1/+1 counter on Talus Paladin.

Crystalline Sliver

All Slivers have shroud. (They can't be the targets of spells or abilities.)

Harabaz Druid

{T}: Add X mana of any one color, where X is the number of Allies you control.

Kabira Evangel

Whenever Kabira Evangel or another Ally enters the battlefield under your control, you may choose a color. If you do, Allies you control gain protection from the chosen color until end of turn.

Kazuul Warlord

Whenever Kazuul Warlord or another Ally enters the battlefield under your control, you may put a +1/+1 counter on each Ally creature you control.

Munda, Ambush Leader

Haste
Rally — Whenever Munda, Ambush Leader or another Ally enters the battlefield under your control, you may look at the top four cards of your library. If you do, reveal any number of Ally cards from among them, then put those cards on top of your library in any order and the rest on the bottom in any order.

Sea Gate Loremaster

{T}: Draw a card for each Ally you control.

Vastwood Animist

{T}: Target land you control becomes an X/X Elemental creature until end of turn, where X is the number of Allies you control. It's still a land.

Mountain

Sliver Gravemother

The "legend rule" doesn't apply to Slivers you control.
Each Sliver creature card in your graveyard has encore {X}, where X is its mana value.
Encore {5} ({5}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Bonescythe Sliver

Sliver creatures you control have double strike. (They deal both first-strike and regular combat damage.)

Tuktuk Scrapper

Whenever Tuktuk Scrapper or another Ally enters the battlefield under your control, you may destroy target artifact. If that artifact is put into a graveyard this way, Tuktuk Scrapper deals damage to that artifact's controller equal to the number of Allies you control.

Frenetic Sliver

All Slivers have "{0}: If this permanent is on the battlefield, flip a coin. If you win the flip, exile this permanent and return it to the battlefield under its owner's control at the beginning of the next end step. If you lose the flip, sacrifice it."

Sliver Legion

All Sliver creatures get +1/+1 for each other Sliver on the battlefield.

Megantic Sliver

Shifting Sliver

Slivers can't be blocked except by Slivers.

Kalastria Healer

Rally — Whenever Kalastria Healer or another Ally enters the battlefield under your control, each opponent loses 1 life and you gain 1 life.

Agadeem Occultist

{T}: Put target creature card from an opponent's graveyard onto the battlefield under your control if its mana value is less than or equal to the number of Allies you control.

Sliver Hivelord

Sliver creatures you control have indestructible. (Damage and effects that say "destroy" don't destroy them.)

Drana's Emissary

Flying
At the beginning of your upkeep, each opponent loses 1 life and you gain 1 life.

Diffusion Sliver

Whenever a Sliver creature you control becomes the target of a spell or ability an opponent controls, counter that spell or ability unless its controller pays {2}.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Spiteful Sliver

Sliver creatures you control have "Whenever this creature is dealt damage, it deals that much damage to target player or planeswalker."

Necrotic Sliver

All Slivers have "{3}, Sacrifice this permanent: Destroy target permanent."

General Tazri

When General Tazri enters the battlefield, you may search your library for an Ally creature card, reveal it, put it into your hand, then shuffle.
{W}{U}{B}{R}{G}: Ally creatures you control get +X/+X until end of turn, where X is the number of colors among those creatures.

Regal Sliver

Sliver creatures you control have "When this creature enters the battlefield, Slivers you control get +1/+1 until end of turn if you're the monarch. Otherwise, you become the monarch."

Bala Ged Thief

Whenever Bala Ged Thief or another Ally enters the battlefield under your control, target player reveals a number of cards from their hand equal to the number of Allies you control. You choose one of them. That player discards that card.

Magma Sliver

All Slivers have "{T}: Target Sliver creature gets +X/+0 until end of turn, where X is the number of Slivers on the battlefield."

Essence Sliver

Whenever a Sliver deals damage, its controller gains that much life.

Drana, Liberator of Malakir

Flying, first strike
Whenever Drana, Liberator of Malakir deals combat damage to a player, put a +1/+1 counter on each attacking creature you control.

Turntimber Ranger

Whenever Turntimber Ranger or another Ally enters the battlefield under your control, you may create a 2/2 green Wolf creature token. If you do, put a +1/+1 counter on Turntimber Ranger.

Hagra Diabolist

Whenever Hagra Diabolist or another Ally enters the battlefield under your control, you may have target player lose life equal to the number of Allies you control.

Brood Sliver

Whenever a Sliver deals combat damage to a player, its controller may create a 1/1 colorless Sliver creature token.

Crypt Sliver

All Slivers have "{T}: Regenerate target Sliver."

Winged Sliver

Halimar Excavator

Whenever Halimar Excavator or another Ally enters the battlefield under your control, target player mills X cards, where X is the number of Allies you control.

Quick Sliver

Flash
Any player may cast Sliver spells as though they had flash.

Syphon Sliver

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

Munda's Vanguard

Cohort — {T}, Tap an untapped Ally you control: Put a +1/+1 counter on each creature you control.

Shadow Sliver

All Sliver creatures have shadow. (They can block or be blocked by only creatures with shadow.)

Mina and Denn, Wildborn

You may play an additional land on each of your turns.
{R}{G}, Return a land you control to its owner's hand: Target creature gains trample until end of turn.