Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Bonesplitter Sliver

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.)

Rukarumel, Biologist

As Rukarumel, Biologist 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.

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Diabolic Tutor

Search your library for a card, put that card into your hand, then shuffle.

Winged Sliver

Harmonic Sliver

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

Crystalline Sliver

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

Demonic Tutor

Brood Sliver

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

Grim Tutor

Search your library for a card, put that card into your hand, then shuffle. You lose 3 life.

Opaline Sliver

All Slivers have "Whenever this permanent becomes the target of a spell an opponent controls, you may draw a card."

Scuttling Sliver

Sliver creatures you control have "{2}: Untap this creature."

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.

Crypt Sliver

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

Poultice Sliver

All Slivers have "{2}, {T}: Regenerate target Sliver." (The next time that Sliver would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

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.)

Sliver Hivelord

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

Pulmonic Sliver

All Sliver creatures have flying.
All Slivers have "If this permanent would be put into a graveyard, you may put it on top of its owner's library instead."

Blur Sliver

Sliver creatures you control have haste. (They can attack and {T} as soon as they come under your control.)

Sliver Legion

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

Might Sliver

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}.

Root Sliver

This spell can't be countered.
Sliver spells can't be countered.

Vampiric Tutor

Search your library for a card, then shuffle and put that card on top. You lose 2 life.