Terminate

Destroy target creature. It can't be regenerated.

Rakdos Signet

Sedraxis Specter

Flying
Whenever Sedraxis Specter deals combat damage to a player, that player discards a card.
Unearth {1}{B} ({1}{B}: Return this card from your graveyard to the battlefield. It gains haste. Exile it at the beginning of the next end step or if it would leave the battlefield. Unearth only as a sorcery.)

Lightning Bolt

Lightning Bolt deals 3 damage to any target.

Shadow Guildmage

{U}, {T}: Put target creature you control on top of its owner's library.
{R}, {T}: Shadow Guildmage deals 1 damage to any target and 1 damage to you.

Duress

Target opponent reveals their hand. You choose a noncreature, nonland card from it. That player discards that card.

Dimir Signet

Izzet Signet

Counterspell

Nightscape Familiar

Blue spells and red spells you cast cost {1} less to cast.
{1}{B}: Regenerate Nightscape Familiar.

Syphon Mind

Each other player discards a card. You draw a card for each card discarded this way.

Village Rites

As an additional cost to cast this spell, sacrifice a creature.
Draw two cards.

Negate

Fleshbag Marauder

When Fleshbag Marauder enters the battlefield, each player sacrifices a creature.

Arcane Signet

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

Preordain

Scry 2, then draw a card. (To scry 2, look at the top two cards of your library, then put any number of them on the bottom and the rest on top in any order.)

Witness Protection

Enchant creature
Enchanted creature loses all abilities and is a green and white Citizen creature with base power and toughness 1/1 named Legitimate Businessperson. (It loses all other colors, card types, creature types, and names.)

Magma Spray

Magma Spray deals 2 damage to target creature. If that creature would die this turn, exile it instead.

Archaeomancer

When Archaeomancer enters the battlefield, return target instant or sorcery card from your graveyard to your hand.

Blightning

Blightning deals 3 damage to target player or planeswalker. That player or that planeswalker's controller discards two cards.

Clout of the Dominus

Enchant creature
As long as enchanted creature is blue, it gets +1/+1 and has shroud. (It can't be the target of spells or abilities.)
As long as enchanted creature is red, it gets +1/+1 and has haste.