Mass Mutiny

For each opponent, gain control of up to one target creature that player controls until end of turn. Untap those creatures. They gain haste until end of turn.

Price of Knowledge

Players have no maximum hand size.
At the beginning of each opponent's upkeep, Price of Knowledge deals damage to that player equal to the number of cards in that player's hand.

Shriveling Rot

Choose one —
• Until end of turn, whenever a creature is dealt damage, destroy it.
• Until end of turn, whenever a creature dies, that creature's controller loses life equal to its toughness.
Entwine {2}{B} (Choose both if you pay the entwine cost.)

Baneful Omen

At the beginning of your end step, you may reveal the top card of your library. If you do, each opponent loses life equal to that card's mana value.

Treacherous Terrain

Treacherous Terrain deals damage to each opponent equal to the number of lands that player controls.
Basic landcycling {2} ({2}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

Yurlok of Scorch Thrash

Vigilance
A player losing unspent mana causes that player to lose that much life.
{1}, {T}: Each player adds {B}{R}{G}.

Nacre Talisman

Whenever a player casts a white spell, you may pay {3}. If you do, untap target permanent.

Belbe, Corrupted Observer

At the beginning of each postcombat main phase, the active player adds {C}{C} for each of your opponents who lost life this turn. (Damage causes loss of life.)

Kaervek the Merciless

Whenever an opponent casts a spell, Kaervek the Merciless deals damage equal to that spell's mana value to any target.

Nightshade Harvester

Whenever a land an opponent controls enters, that player loses 1 life. Put a +1/+1 counter on Nightshade Harvester.

Witch Hunt

Players can't gain life.
At the beginning of your upkeep, Witch Hunt deals 4 damage to you.
At the beginning of your end step, target opponent chosen at random gains control of Witch Hunt.

Primal Order

At the beginning of each player's upkeep, Primal Order deals damage to that player equal to the number of nonbasic lands they control.

Seeker of Skybreak

Lavalanche

Lavalanche deals X damage to target player or planeswalker and each creature that player or that planeswalker's controller controls.

Pestilence Demon

Flying
{B}: Pestilence Demon deals 1 damage to each creature and each player.

Alpha Brawl

Target creature an opponent controls deals damage equal to its power to each other creature that player controls, then each of those creatures deals damage equal to its power to that creature.

Final Punishment

Target player loses life equal to the damage already dealt to that player this turn.

Malachite Talisman

Whenever a player casts a green spell, you may pay {3}. If you do, untap target permanent.

Wall of Souls

Defender (This creature can't attack.)
Whenever Wall of Souls is dealt combat damage, it deals that much damage to target opponent or planeswalker.

Din of the Fireherd

Create a 5/5 black and red Elemental creature token. Target opponent sacrifices a creature of their choice for each black creature you control, then sacrifices a land of their choice for each red creature you control.

Hematite Talisman

Whenever a player casts a red spell, you may pay {3}. If you do, untap target permanent.

Ribbons

Aftermath (Cast this spell only from your graveyard. Then exile it.)
Each opponent loses X life.

Cut // Ribbons

Lapis Lazuli Talisman

Whenever a player casts a blue spell, you may pay {3}. If you do, untap target permanent.

Curtains' Call

Undaunted (This spell costs {1} less to cast for each opponent.)
Destroy two target creatures.

Stoneshaker Shaman

At the beginning of each player's end step, that player sacrifices an untapped land of their choice.

Instill Energy

Enchant creature
Enchanted creature can attack as though it had haste.
{0}: Untap enchanted creature. Activate only during your turn and only once each turn.

Havoc Festival

Players can't gain life.
At the beginning of each player's upkeep, that player loses half their life, rounded up.

Delirium

Cast this spell only during an opponent's turn.
Tap target creature that player controls. That creature deals damage equal to its power to the player. Prevent all combat damage that would be dealt to and dealt by the creature this turn.

Seeds of Renewal

Undaunted (This spell costs {1} less to cast for each opponent.)
Return up to two target cards from your graveyard to your hand. Exile Seeds of Renewal.

Aether Sting

Whenever an opponent casts a creature spell, Aether Sting deals 1 damage to that player.

Power Surge

At the beginning of each player's upkeep, Power Surge deals X damage to that player, where X is the number of untapped lands they controlled at the beginning of this turn.

Onyx Talisman

Whenever a player casts a black spell, you may pay {3}. If you do, untap target permanent.

Phthisis

Destroy target creature. Its controller loses life equal to its power plus its toughness.
Suspend 5—{1}{B} (Rather than cast this card from your hand, you may pay {1}{B} and exile it with five 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.)

Magmatic Force

At the beginning of each upkeep, Magmatic Force deals 3 damage to any target.

Grave Endeavor

Roll two d10 and choose one result. Return a creature card from your graveyard to the battlefield with a number of +1/+1 counters on it equal to that result. Then each opponent loses X life and you gain X life, where X is the other result.

Breath of Malfegor

Breath of Malfegor deals 5 damage to each opponent.

Decree of Pain

Destroy all creatures. They can't be regenerated. Draw a card for each creature destroyed this way.
Cycling {3}{B}{B} ({3}{B}{B}, Discard this card: Draw a card.)
When you cycle Decree of Pain, all creatures get -2/-2 until end of turn.