Total War

Whenever a player attacks with one or more creatures, destroy all untapped non-Wall creatures that player controls that didn't attack, except for creatures the player hasn't controlled continuously since the beginning of the turn.

Melee

Cast this spell only during your turn and only during combat before blockers are declared.
You choose which creatures block this combat and how those creatures block.
Whenever a creature attacks and isn't blocked this combat, untap it and remove it from combat.

Price of Glory

Whenever a player taps a land for mana, if it's not that player's turn, destroy that land.

Tajic, Blade of the Legion

Indestructible
Battalion — Whenever Tajic, Blade of the Legion and at least two other creatures attack, Tajic gets +5/+5 until end of turn.

Possibility Storm

Whenever a player casts a spell from their hand, that player exiles it, then exiles cards from the top of their library until they exile a card that shares a card type with it. That player may cast that card without paying its mana cost. Then they put all cards exiled with Possibility Storm on the bottom of their library in a random order.

Chaos Moon

At the beginning of each upkeep, count the number of permanents. If the number is odd, until end of turn, red creatures get +1/+1 and whenever a player taps a Mountain for mana, that player adds an additional {R}. If the number is even, until end of turn, red creatures get -1/-1 and if a player taps a Mountain for mana, that Mountain produces colorless mana instead of any other type.

Hand to Hand

During combat, players can't cast instant spells or activate abilities that aren't mana abilities.

Planar Chaos

At the beginning of your upkeep, flip a coin. If you lose the flip, sacrifice Planar Chaos.
Whenever a player casts a spell, that player flips a coin. If they lose the flip, counter that spell.

Chaosphere

Creatures with flying can block only creatures with flying.
Creatures without flying have reach. (They can block creatures with flying.)

No Quarter

Whenever a creature becomes blocked by a creature with lesser power, destroy the blocking creature.
Whenever a creature blocks a creature with lesser power, destroy the attacking creature.

Bedlam Reveler

This spell costs {1} less to cast for each instant and sorcery card in your graveyard.
Prowess
When Bedlam Reveler enters, discard your hand, then draw three cards.

Pandemonium

Whenever a creature enters, that creature's controller may have it deal damage equal to its power to any target of their choice.

Custody Battle

Enchant creature
Enchanted creature has "At the beginning of your upkeep, target opponent gains control of this creature unless you sacrifice a land."

Dwarven Armory

{2}, Sacrifice a land: Put a +2/+2 counter on target creature. Activate only during any upkeep step.

Heat Stroke

At end of combat, destroy each creature that blocked or was blocked this turn.

Repercussion

Whenever a creature is dealt damage, Repercussion deals that much damage to that creature's controller.

Invasion Plans

All creatures block each combat if able.
The attacking player chooses how each creature blocks each combat.

Brand of Ill Omen

Enchant creature
Cumulative upkeep {R} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
Enchanted creature's controller can't cast creature spells.

Burning Sands

Whenever a creature dies, that creature's controller sacrifices a land of their choice.

Grand Melee

All creatures attack each combat if able.
All creatures block each combat if able.

Bedlam

Confusion in the Ranks

Whenever an artifact, creature, or enchantment enters, its controller chooses target permanent another player controls that shares a card type with it. Exchange control of those permanents.

Heat of Battle

Whenever a creature blocks, Heat of Battle deals 1 damage to that creature's controller.

Risky Move

At the beginning of each player's upkeep, that player gains control of Risky Move.
When you gain control of Risky Move from another player, choose a creature you control and an opponent. Flip a coin. If you lose the flip, that opponent gains control of that creature.