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.

Acidic Sliver

All Slivers have "{2}, Sacrifice this permanent: This permanent deals 2 damage to any target."

Basal Sliver

All Slivers have "Sacrifice this permanent: Add {B}{B}."

Manaweft Sliver

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

Crystalline Sliver

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