Unexpected Potential

Hidden agenda (Start the game with this conspiracy face down in the command zone and secretly choose a card name. You may turn this conspiracy face up any time and reveal that name.)
You may spend mana as though it were mana of any color to cast spells with the chosen name.

Fires of Yavimaya

Creatures you control have haste.
Sacrifice Fires of Yavimaya: Target creature gets +2/+2 until end of turn.

Demigod of Revenge

When you cast this spell, return all cards named Demigod of Revenge from your graveyard to the battlefield.
Flying, haste

Riku of Two Reflections

Whenever you cast an instant or sorcery spell, you may pay . If you do, copy that spell. You may choose new targets for the copy.
Whenever another nontoken creature you control enters, you may pay . If you do, create a token that’s a copy of that creature.

Riku of Two Reflections

Whenever you cast an instant or sorcery spell, you may pay . If you do, copy that spell. You may choose new targets for the copy.
Whenever another nontoken creature you control enters, you may pay . If you do, create a token that’s a copy of that creature.

Sin Collector

When Sin Collector enters, target opponent reveals their hand. You choose an instant or sorcery card from it and exile that card.

Greed

, Pay 2 life: Draw a card.

Deceiver Exarch

Flash (You may cast this spell any time you could cast an instant.)
When Deceiver Exarch enters, choose one —
• Untap target permanent you control.
• Tap target permanent an opponent controls.

Blue Sun’s Zenith

Target player draws X cards. Shuffle Blue Sun’s Zenith into its owner’s library.

Sharuum the Hegemon

Flying
When Sharuum the Hegemon enters, you may return target artifact card from your graveyard to the battlefield.

Fires of Yavimaya

Creatures you control have haste.
Sacrifice Fires of Yavimaya: Target creature gets +2/+2 until end of turn.

Jade Mage

: Create a 1/1 green Saproling creature token.

Winged Coatl

Flash (You may cast this spell any time you could cast an instant.)
Flying
Deathtouch (Any amount of damage this deals to a creature is enough to destroy it.)

Sharuum the Hegemon

Flying
When Sharuum the Hegemon enters, you may return target artifact card from your graveyard to the battlefield.

Fires of Yavimaya

Creatures you control have haste.
Sacrifice Fires of Yavimaya: Target creature gets +2/+2 until end of turn.

Impulse

Look at the top four cards of your library. Put one of them into your hand and the rest on the bottom of your library in any order.

Haunted Plate Mail

Equipped creature gets +4/+4.
: Until end of turn, Haunted Plate Mail becomes a 4/4 Spirit artifact creature that’s no longer an Equipment. Activate only if you control no creatures.
Equip (: Attach to target creature you control. Equip only as a sorcery.)

Wring Flesh

Target creature gets -3/-1 until end of turn.

Ethersworn Canonist

Each player who has cast a nonartifact spell this turn can’t cast additional nonartifact spells.

Phytoburst

Target creature gets +5/+5 until end of turn.

Cancel

Counter target spell.

Sin Collector

When Sin Collector enters, target opponent reveals their hand. You choose an instant or sorcery card from it and exile that card.