Two-Headed Sliver

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

Striking Sliver

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

Door of Destinies

As Door of Destinies enters, choose a creature type.
Whenever you cast a spell of the chosen type, put a charge counter on Door of Destinies.
Creatures you control of the chosen type get +1/+1 for each charge counter on Door of Destinies.

Muscle Sliver

Sinew Sliver

Megantic Sliver

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.

Quick Sliver

Flash
Any player may cast Sliver spells as though they had flash.

Homing Sliver

Each Sliver card in each player's hand has slivercycling {3}.
Slivercycling {3} ({3}, Discard this card: Search your library for a Sliver card, reveal it, put it into your hand, then shuffle.)

Predatory Sliver

Venom Sliver

Sliver creatures you control have deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Gemhide Sliver

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

Sentinel Sliver

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

Constricting Sliver

Sliver creatures you control have "When this creature enters, you may exile target creature an opponent controls until this creature leaves the battlefield."

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.)

Sliver Legion

All Sliver creatures get +1/+1 for each other Sliver on the battlefield.

Winged Sliver

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.)

Might Sliver

Sliver Hivelord

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

Brood Sliver

Whenever a Sliver deals combat damage to a player, its controller may create a 1/1 colorless Sliver creature token.

Necrotic Sliver

All Slivers have "{3}, Sacrifice this permanent: Destroy target permanent."

Shifting Sliver

Slivers can't be blocked except by Slivers.

Spiteful Sliver

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

Heart Sliver

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Harmonic Sliver

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

Morophon, the Boundless

Changeling (This card is every creature type.)
As Morophon, the Boundless enters, choose a creature type.
Spells of the chosen type you cast cost {W}{U}{B}{R}{G} less to cast. This effect reduces only the amount of colored mana you pay.
Other creatures you control of the chosen type get +1/+1.