Withering Boon

As an additional cost to cast this spell, pay 3 life.
Counter target creature spell.

Jeska's Will

Choose one. If you control a commander as you cast this spell, you may choose both instead.
• Add {R} for each card in target opponent's hand.
• Exile the top three cards of your library. You may play them this turn.

Deflecting Swat

If you control a commander, you may cast this spell without paying its mana cost.
You may choose new targets for target spell or ability.

The Abyss

At the beginning of each player's upkeep, destroy target nonartifact creature that player controls of their choice. It can't be regenerated.

Tortured Existence

{B}, Discard a creature card: Return target creature card from your graveyard to your hand.

Fork

Copy target instant or sorcery spell, except that the copy is red. You may choose new targets for the copy.

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.

Swords to Plowshares

Exile target creature. Its controller gains life equal to its power.

Esper Sentinel

Whenever an opponent casts their first noncreature spell each turn, draw a card unless that player pays {X}, where X is Esper Sentinel's power.

Rubblebelt Maaka

Bloodrush — {R}, Discard Rubblebelt Maaka: Target attacking creature gets +3/+3 until end of turn.

Awaken the Blood Avatar

As an additional cost to cast this spell, you may sacrifice any number of creatures. This spell costs {2} less to cast for each creature sacrificed this way.
Each opponent sacrifices a creature. Create a 3/6 black and red Avatar creature token with haste and "Whenever this creature attacks, it deals 3 damage to each opponent."

Extus, Oriq Overlord

Double strike
Magecraft — Whenever you cast or copy an instant or sorcery spell, return target nonlegendary creature card from your graveyard to your hand.

Extus, Oriq Overlord // Awaken the Blood Avatar

Priest of Forgotten Gods

{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature. You add {B}{B} and draw a card.

Urborg Justice

Target opponent sacrifices a creature for each creature put into your graveyard from the battlefield this turn.

Entomb

Search your library for a card, put that card into your graveyard, then shuffle.

Hurl Through Hell

Exile target creature. Until the end of your next turn, you may cast that card and you may spend mana as though it were mana of any color to cast that spell.

Teferi's Protection

Until your next turn, your life total can't change and you gain protection from everything. All permanents you control phase out. (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.)
Exile Teferi's Protection.

Skinbrand Goblin

Bloodrush — {R}, Discard Skinbrand Goblin: Target attacking creature gets +2/+1 until end of turn.

Dockside Extortionist

When Dockside Extortionist enters, create X Treasure tokens, where X is the number of artifacts and enchantments your opponents control. (Treasure tokens are artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Bog Witch

Orcish Bowmasters

Flash
When Orcish Bowmasters enters and whenever an opponent draws a card except the first one they draw in each of their draw steps, Orcish Bowmasters deals 1 damage to any target. Then amass Orcs 1.