Dictate of the Twin Gods

Flash
If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.

Overblaze

Each time target permanent would deal damage to a permanent or player this turn, it deals double that damage to that permanent or player instead.
Splice onto Arcane {2}{R}{R} (As you cast an Arcane spell, you may reveal this card from your hand and pay its splice cost. If you do, add this card's effects to that spell.)

Worldfire

Exile all permanents. Exile all cards from all hands and graveyards. Each player's life total becomes 1.

Apocalypse

Exile all permanents. You discard your hand.

Silent Arbiter

No more than one creature can attack each combat.
No more than one creature can block each combat.

Red Elemental Blast

Choose one —
• Counter target blue spell.
• Destroy target blue permanent.

Sol Ring

Grapeshot

Grapeshot deals 1 damage to any target.
Storm (When you cast this spell, copy it for each spell cast before it this turn. You may choose new targets for the copies.)

Mana Geyser

Add {R} for each tapped land your opponents control.

Reiterate

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.)
Copy target instant or sorcery spell. You may choose new targets for the copy.

Magus of the Moon

Heartless Hidetsugu

{T}: Heartless Hidetsugu deals damage to each player equal to half that player's life total, rounded down.

Skullcrack

Players can't gain life this turn. Damage can't be prevented this turn. Skullcrack deals 3 damage to target player or planeswalker.

Anger

Haste
As long as Anger is in your graveyard and you control a Mountain, creatures you control have haste.

Reverberate

Copy target instant or sorcery spell. You may choose new targets for the copy.

Mountain

Treasonous Ogre

Dethrone (Whenever this creature attacks the player with the most life or tied for most life, put a +1/+1 counter on it.)
Pay 3 life: Add {R}.

Price of Progress

Price of Progress deals damage to each player equal to twice the number of nonbasic lands that player controls.

Warp World

Each player shuffles all permanents they own into their library, then reveals that many cards from the top of their library. Each player puts all artifact, creature, and land cards revealed this way onto the battlefield, then does the same for enchantment cards, then puts all cards revealed this way that weren't put onto the battlefield on the bottom of their library.

Blood Moon

Furnace of Rath

If a source would deal damage to a permanent or player, it deals double that damage to that permanent or player instead.