Sliver Gravemother

The "legend rule" doesn't apply to Slivers you control.
Each Sliver creature card in your graveyard has encore {X}, where X is its mana value.
Encore {5} ({5}, Exile this card from your graveyard: For each opponent, create a token copy that attacks that opponent this turn if able. They gain haste. Sacrifice them at the beginning of the next end step. Activate only as a sorcery.)

Acidic Sliver

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

Chromatic Lantern

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

Herald's Horn

As Herald's Horn enters, choose a creature type.
Creature spells you cast of the chosen type cost {1} less to cast.
At the beginning of your upkeep, look at the top card of your library. If it's a creature card of the chosen type, you may reveal it and put it into your hand.

Path of Ancestry

Path of Ancestry enters tapped.
{T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Mana Crypt

At the beginning of your upkeep, flip a coin. If you lose the flip, Mana Crypt deals 3 damage to you.
{T}: Add {C}{C}.

Sliver Legion

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

Cyclonic Rift

Return target nonland permanent you don't control to its owner's hand.
Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Path to Exile

Exile target creature. Its controller may search their library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Toxin Sliver

Whenever a Sliver deals combat damage to a creature, destroy that creature. It can't be regenerated.

Sol Ring

Rejuvenating Springs

Rejuvenating Springs enters tapped unless you have two or more opponents.
{T}: Add {G} or {U}.

The One Ring

Indestructible
When The One Ring enters, if you cast it, you gain protection from everything until your next turn.
At the beginning of your upkeep, you lose 1 life for each burden counter on The One Ring.
{T}: Put a burden counter on The One Ring, then draw a card for each burden counter on The One Ring.

Taunting Sliver

Sliver creatures you control have "When this creature enters, goad target creature an opponent controls." (Until your next turn, that creature attacks each combat if able and attacks a player other than you if able.)

Secluded Courtyard

As Secluded Courtyard enters, choose a creature type.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a creature spell of the chosen type or activate an ability of a creature source of the chosen type.

Shadow Sliver

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

Jeweled Lotus

{T}, Sacrifice Jeweled Lotus: Add three mana of any one color. Spend this mana only to cast your commander.

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.)

Essence Sliver

Whenever a Sliver deals damage, its controller gains that much life.

Command Tower

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

Sinew Sliver

Spectator Seating

Spectator Seating enters tapped unless you have two or more opponents.
{T}: Add {R} or {W}.

Three Visits

Search your library for a Forest card, put it onto the battlefield, then shuffle.

Screeching Sliver

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

Roaming Throne

Ward {2}
As Roaming Throne enters, choose a creature type.
Roaming Throne is the chosen type in addition to its other types.
If a triggered ability of another creature you control of the chosen type triggers, it triggers an additional time.

Harmonic Sliver

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

Crystalline Sliver

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

Mox Tantalite

Suspend 3—{0} (Rather than cast this card from your hand, pay {0} and exile it with three time counters on it. At the beginning of your upkeep, remove a time counter. When the last is removed, you may cast it without paying its mana cost.)
{T}: Add one mana of any color.

Manaweft Sliver

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

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.

Ghostflame Sliver

Cloudshredder Sliver

Sliver creatures you control have flying and haste.

Vandalblast

Destroy target artifact you don't control.
Overload {4}{R} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Bonescythe Sliver

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

Necrotic Sliver

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

Otawara, Soaring City

{T}: Add {U}.
Channel — {3}{U}, Discard Otawara, Soaring City: Return target artifact, creature, enchantment, or planeswalker to its owner's hand. This ability costs {1} less to activate for each legendary creature you control.

Training Center

Training Center enters tapped unless you have two or more opponents.
{T}: Add {U} or {R}.