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."

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."

Zinnia, Valley's Voice

Flying
Zinnia gets +X/+0, where X is the number of other creatures you control with base power 1.
Creature spells you cast gain offspring {2} as you cast them. (You may pay an additional {2} as you cast a creature spell. If you do, when that creature enters, create a 1/1 token copy of it.)

Fury Sliver

Lancer Sliver

Sliver creatures you control have first strike.

Sentinel Sliver

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

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Blur Sliver

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

Bonescythe Sliver

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

Heart 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}.

Shifting Sliver

Slivers can't be blocked except by Slivers.

Galerider Sliver

Sliver creatures you control have flying.

Cleaving Sliver

Thrumming Hivepool

Affinity for Slivers (This spell costs {1} less to cast for each Sliver you control.)
Slivers you control have double strike and haste.
At the beginning of your upkeep, create two 1/1 colorless Sliver creature tokens.