Rukarumel, Biologist

As Rukarumel enters, 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.

Horned Sliver

Fungus Sliver

All Sliver creatures have "Whenever this creature is dealt damage, put a +1/+1 counter on it." (It must survive the damage to get the counter.)

Hibernation Sliver

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

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Crypt Sliver

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

Bonescythe Sliver

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

Helm of the Host

At the beginning of combat on your turn, create a token that's a copy of equipped creature, except the token isn't legendary. That token gains haste.
Equip {5}

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.)

Kambal, Profiteering Mayor

Whenever one or more tokens your opponents control enter, for each of them, create a tapped token that's a copy of it. This ability triggers only once each turn.
Whenever one or more tokens you control enter, each opponent loses 1 life and you gain 1 life.

Jwari Shapeshifter

You may have this creature enter as a copy of any Ally creature on the battlefield.

Sakashima the Impostor

You may have Sakashima the Impostor enter as a copy of any creature on the battlefield, except its name is Sakashima the Impostor, it's legendary in addition to its other types, and it has "{2}{U}{U}: Return Sakashima the Impostor to its owner's hand at the beginning of the next end step."

Extravagant Replication

At the beginning of your upkeep, create a token that's a copy of another target nonland permanent you control.

Sakashima of a Thousand Faces

You may have Sakashima enter as a copy of another creature you control, except it has Sakashima's other abilities.
The "legend rule" doesn't apply to permanents you control.
Partner (You can have two commanders if both have partner.)

Quick Sliver

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

Shifting Sliver

Slivers can't be blocked except by Slivers.

Ally Encampment

{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast an Ally spell.
{1}, {T}, Sacrifice this land: Return target Ally you control to its owner's hand.

Mesmeric Sliver

All Slivers have "When this permanent enters, you may fateseal 1." (To fateseal 1, its controller looks at the top card of an opponent's library, then they may put that card on the bottom of that library.)

Double Major

Copy target creature spell you control, except it isn't legendary if the spell is legendary. (A copy of a creature spell becomes a token.)

Galerider Sliver

Sliver creatures you control have flying.

Heart Sliver

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.)

Spined Sliver

Whenever a Sliver becomes blocked, that Sliver gets +1/+1 until end of turn for each creature blocking it.

Manaweft Sliver

Sliver creatures you control have "{T}: Add one mana of any color."

Lazotep Sliver

Sliver creatures you control have afflict 2. (Whenever a creature with afflict 2 becomes blocked, defending player loses 2 life.)
Whenever a nontoken Sliver you control dies, amass Slivers 2. (Put two +1/+1 counters on an Army you control. It's also a Sliver. If you don't control an Army, create a 0/0 black Sliver Army creature token first.)

Sliver Hivelord

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

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.)

Gemhide Sliver

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

Sentinel Sliver

Sliver creatures you control have vigilance. (Attacking doesn't cause them to tap.)

Sliver Legion

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

Kalastria Healer

Rally — Whenever this creature or another Ally you control enters, each opponent loses 1 life and you gain 1 life.

Harmonic Sliver

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

Hatchery Sliver

Replicate {1}{G} (When you cast this spell, copy it for each time you paid its replicate cost.)
Each Sliver spell you cast has replicate. The replicate cost is equal to its mana cost. (A copy of a permanent spell becomes a token.)

Essence Sliver

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

Sidewinder Sliver

All Sliver creatures have flanking. (Whenever a creature without flanking blocks a Sliver, the blocking creature gets -1/-1 until end of turn.)

Clot Sliver

All Slivers have "{2}: Regenerate this permanent."

Crystalline Sliver

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

Striking Sliver

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

Virulent Sliver

All Sliver creatures have poisonous 1. (Whenever a Sliver deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)

Muscle Sliver

Mockingbird

Flying
You may have this creature enter as a copy of any creature on the battlefield with mana value less than or equal to the amount of mana spent to cast this creature, except it's a Bird in addition to its other types and it has flying.

Two-Headed Sliver

All Sliver creatures have menace. (They can't be blocked except by two or more creatures.)

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.

Sliver Queen

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

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}.

Irenicus's Vile Duplication

Create a token that's a copy of target creature you control, except the token has flying and it isn't legendary.

Spinneret Sliver

Syphon Sliver

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