Mana Flare

Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

Golos, Tireless Pilgrim

When Golos, Tireless Pilgrim 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.

Dryad of the Ilysian Grove

You may play an additional land on each of your turns.
Lands you control are every basic land type in addition to their other types.

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.

Zendikar Resurgent

Whenever you tap a land for mana, add one mana of any type that land produced. (The types of mana are white, blue, black, red, green, and colorless.)
Whenever you cast a creature spell, draw a card.

Painful Truths

Converge — You draw X cards and you lose X life, where X is the number of colors of mana spent to cast this spell.

Chromatic Lantern

Lands you control have "{T}: Add one mana of any color."
{T}: Add one mana of any color.

Rise of the Dark Realms

Put all creature cards from all graveyards onto the battlefield under your control.

Fist of Suns

You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Treasure Cove

(Transforms from Treasure Map.)
{T}: Add {C}.
{T}, Sacrifice a Treasure: Draw a card.

Treasure Map

{1}, {T}: Scry 1. Put a landmark counter on Treasure Map. Then if there are three or more landmark counters on it, remove those counters, transform Treasure Map, and create three Treasure tokens. (They're artifacts with "{T}, Sacrifice this artifact: Add one mana of any color.")

Treasure Map // Treasure Cove

Inspired Ultimatum

Target player gains 5 life, Inspired Ultimatum deals 5 damage to any target, then you draw five cards.

Spelltwine

Exile target instant or sorcery card from your graveyard and target instant or sorcery card from an opponent's graveyard. Copy those cards. Cast the copies if able without paying their mana costs. Exile Spelltwine.

Jodah, Archmage Eternal

Flying
You may pay {W}{U}{B}{R}{G} rather than pay the mana cost for spells you cast.

Sunbird's Invocation

Whenever you cast a spell from your hand, reveal the top X cards of your library, where X is that spell's mana value. You may cast a spell with mana value X or less from among cards revealed this way without paying its mana cost. Put the rest on the bottom of your library in a random order.

Bonus Round

Until end of turn, whenever a player casts an instant or sorcery spell, that player copies it and may choose new targets for the copy.

Cruel Ultimatum

Target opponent sacrifices a creature, discards three cards, then loses 5 life. You return a creature card from your graveyard to your hand, draw three cards, then gain 5 life.

Nezahal, Primal Tide

This spell can't be countered.
You have no maximum hand size.
Whenever an opponent casts a noncreature spell, draw a card.
Discard three cards: Exile Nezahal, Primal Tide. Return it to the battlefield tapped under its owner's control at the beginning of the next end step.

Quicksilver Amulet

{4}, {T}: You may put a creature card from your hand onto the battlefield.

Duneblast

Choose up to one creature. Destroy the rest.

Rite of Ruin

Choose an order for artifacts, creatures, and lands. Each player sacrifices one permanent of the first type, sacrifices two of the second type, then sacrifices three of the third type.

Emergent Ultimatum

Search your library for up to three monocolored cards with different names and exile them. An opponent chooses one of those cards. Shuffle that card into your library. You may cast the other cards without paying their mana costs. Exile Emergent Ultimatum.

Sepulchral Primordial

Intimidate (This creature can't be blocked except by artifact creatures and/or creatures that share a color with it.)
When Sepulchral Primordial enters, for each opponent, you may put up to one target creature card from that player's graveyard onto the battlefield under your control.

Genesis Ultimatum

Look at the top five cards of your library. Put any number of permanent cards from among them onto the battlefield and the rest into your hand. Exile Genesis Ultimatum.

Brass's Bounty

For each land you control, create a Treasure token. (It's an artifact with "{T}, Sacrifice this artifact: Add one mana of any color.")

Dictate of Karametra

Flash
Whenever a player taps a land for mana, that player adds one mana of any type that land produced.

In Garruk's Wake

Destroy all creatures you don't control and all planeswalkers you don't control.

Maelstrom Archangel

Flying
Whenever Maelstrom Archangel deals combat damage to a player, you may cast a spell from your hand without paying its mana cost.

Bringer of the Black Dawn

You may pay {W}{U}{B}{R}{G} rather than pay this spell's mana cost.
Trample
At the beginning of your upkeep, you may pay 2 life. If you do, search your library for a card, then shuffle and put that card on top.

Brilliant Ultimatum

Exile the top five cards of your library. An opponent separates those cards into two piles. You may play lands and cast spells from one of those piles. If you cast a spell this way, you cast it without paying its mana cost.

Torrential Gearhulk

Flash
When Torrential Gearhulk enters, you may cast target instant card from your graveyard without paying its mana cost. If that spell would be put into your graveyard, exile it instead.

Eerie Ultimatum

Return any number of permanent cards with different names from your graveyard to the battlefield.

Door to Nothingness

Door to Nothingness enters tapped.
{W}{W}{U}{U}{B}{B}{R}{R}{G}{G}, {T}, Sacrifice Door to Nothingness: Target player loses the game.

Swarm Intelligence

Whenever you cast an instant or sorcery spell, you may copy that spell. You may choose new targets for the copy.

Progenitus

Protection from everything
If Progenitus would be put into a graveyard from anywhere, reveal Progenitus and shuffle it into its owner's library instead.