Manaweft Sliver

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

Darkheart Sliver

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

Striking Sliver

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

Predatory Sliver

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Reflections of Littjara

As Reflections of Littjara enters, choose a creature type.
Whenever you cast a spell of the chosen type, copy that spell. (A copy of a permanent spell becomes a token.)

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Shifting Sliver

Slivers can't be blocked except by Slivers.

Sliver Hivelord

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

Sol Ring

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."

Harmonic Sliver

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

Crypt Sliver

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

Spiteful Sliver

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

Cultivate

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.