Negate

Snap

Return target creature to its owner's hand. Untap up to two lands.

Groundswell

Target creature gets +2/+2 until end of turn.
Landfall — If you had a land enter the battlefield under your control this turn, that creature gets +4/+4 until end of turn instead.

Shadow Sliver

All Sliver creatures have shadow. (They can block or be blocked by only creatures with shadow.)

Virulent Sliver

All Sliver creatures have poisonous 1. (Whenever a Sliver deals combat damage to a player, that player gets a poison counter. A player with ten or more poison counters loses the game.)

Island

Horned Sliver

Winged Sliver

Predatory Sliver

Muscle Sliver

Synchronous Sliver

Counterspell

Screeching Sliver

All Slivers have "{T}: Target player mills a card."

Gemhide Sliver

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