Two-Headed Sliver

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

Cautery Sliver

All Slivers have "{1}, Sacrifice this permanent: This permanent deals 1 damage to any target."
All Slivers have "{1}, Sacrifice this permanent: Prevent the next 1 damage that would be dealt to target player, planeswalker, or Sliver creature this turn."

Dormant Sliver

All Sliver creatures have defender.
All Slivers have "When this permanent enters, draw a card."

Hivestone

Creatures you control are Slivers in addition to their other creature types.

Hollowhead Sliver

Sliver creatures you control have "{T}, Discard a card: Draw a card."

First Sliver's Chosen

Sliver creatures you control have exalted. (Whenever a creature you control attacks alone, it gets +1/+1 until end of turn for each instance of exalted among permanents you control.)

Poultice Sliver

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

Spinneret Sliver

Gemhide Sliver

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

Lymph Sliver

All Sliver creatures have absorb 1. (If a source would deal damage to a Sliver, prevent 1 of that damage.)

Cleaving Sliver

Darkheart Sliver

All Slivers have "Sacrifice this permanent: You gain 3 life."

Reflex Sliver

Scuttling Sliver

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

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.)

Dregscape Sliver

Each Sliver creature card in your graveyard has unearth {2}.
Unearth {2} ({2}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

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.

Might Sliver

Tempered Sliver

Sliver creatures you control have "Whenever this creature deals combat damage to a player, put a +1/+1 counter on it."

Sinew Sliver

Lavabelly Sliver

Sliver creatures you control have "When this creature enters, it deals 1 damage to target player or planeswalker and you gain 1 life."

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Bonesplitter Sliver

Watcher Sliver

Battering Sliver

Muscle Sliver

Fury Sliver

Harmonic Sliver

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

Firewake Sliver

All Sliver creatures have haste.
All Slivers have "{1}, Sacrifice this permanent: Target Sliver creature gets +2/+2 until end of turn."

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.)