Paradox Engine

Whenever you cast a spell, untap all nonland permanents you control.

Swamp

Hullbreacher

Flash
If an opponent would draw a card except the first one they draw in each of their draw steps, instead you create a Treasure token. (It's an artifact with "{T}, Sacrifice this token: Add one mana of any color.")

Nadu, Winged Wisdom

Flying
Creatures you control have "Whenever this creature becomes the target of a spell or ability, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put it into your hand. This ability triggers only twice each turn."

Island

Plains

Golos, Tireless Pilgrim

When Golos enters, you may search your library for a land card, put that card onto the battlefield tapped, then shuffle.
{2}{W}{U}{B}{R}{G}: Exile the top three cards of your library. You may play them this turn without paying their mana costs.

Balance

Each player chooses a number of lands they control equal to the number of lands controlled by the player who controls the fewest, then sacrifices the rest. Players discard cards and sacrifice creatures the same way.

Limited Resources

When this enchantment enters, each player chooses five lands they control and sacrifices the rest.
Players can't play lands as long as ten or more lands are on the battlefield.

Trade Secrets

Target opponent draws two cards, then you draw up to four cards. That opponent may repeat this process as many times as they choose.

Karakas

{T}: Add {W}.
{T}: Return target legendary creature to its owner's hand.

Forest

Upheaval

Return all permanents to their owners' hands.

Sundering Titan

When this creature enters or leaves the battlefield, choose a land of each basic land type, then destroy those lands.

Jeweled Lotus

{T}, Sacrifice this artifact: Add three mana of any one color. Spend this mana only to cast your commander.

Mountain

Biorhythm

Each player's life total becomes the number of creatures they control.

Treasure

{T}, Sacrifice this token: Add one mana of any color.

Dockside Extortionist

When this creature 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 token: Add one mana of any color.")

Prophet of Kruphix

Untap all creatures and lands you control during each other player's untap step.
You may cast creature spells as though they had flash.