Metallic Sliver

Fevered Convulsions

{2}{B}{B}: Put a -1/-1 counter on target creature.

Lobotomy

Target player reveals their hand, then you choose a card other than a basic land card from it. Search that player's graveyard, hand, and library for all cards with the same name as the chosen card and exile them. Then that player shuffles.

Power Sink

Counter target spell unless its controller pays {X}. If that player doesn't, they tap all lands with mana abilities they control and lose all unspent mana.

Extinction

Destroy all creatures of the creature type of your choice.

Clot Sliver

All Slivers have "{2}: Regenerate this permanent."

Rootwater Depths

{T}: Add {C}.
{T}: Add {U} or {B}. Rootwater Depths doesn't untap during your next untap step.

Evincar's Justice

Buyback {3} (You may pay an additional {3} as you cast this spell. If you do, put this card into your hand as it resolves.)
Evincar's Justice deals 2 damage to each creature and each player.

Whispers of the Muse

Buyback {5} (You may pay an additional {5} as you cast this spell. If you do, put this card into your hand as it resolves.)
Draw a card.

Dream Cache

Draw three cards, then put two cards from your hand both on top of your library or both on the bottom of your library.

Dismiss

Dark Banishing

Destroy target nonblack creature. It can't be regenerated.

Diabolic Edict

Target player sacrifices a creature of their choice.

Counterspell

Island

Winged Sliver

Spell Blast

Counter target spell with mana value X. (For example, if that spell's mana cost is {3}{U}{U}, X is 5.)

Essence Bottle

{3}, {T}: Put an elixir counter on Essence Bottle.
{T}, Remove all elixir counters from Essence Bottle: You gain 2 life for each elixir counter removed this way.

Mnemonic Sliver

All Slivers have "{2}, Sacrifice this permanent: Draw a card."

Swamp

Mindwhip Sliver

All Slivers have "{2}, Sacrifice this permanent: Target player discards a card at random. Activate only as a sorcery."

Ertai's Meddling

X can't be 0.
Target spell's controller exiles it with X delay counters on it.
At the beginning of each of that player's upkeeps, if that card is exiled, remove a delay counter from it. If the card has no delay counters on it, the player puts it onto the stack as a copy of the original spell.