Primeval Spawn

If Primeval Spawn would enter the battlefield and it wasn't cast or no mana was spent to cast it, exile it instead.
Vigilance, trample, lifelink
When Primeval Spawn leaves the battlefield, exile the top ten cards of your library. You may cast any number of spells with total mana value 10 or less from among them without paying their mana costs.

Chromanticore

Bestow {2}{W}{U}{B}{R}{G} (If you cast this card for its bestow cost, it's an Aura spell with enchant creature. It becomes a creature again if it's not attached to a creature.)
Flying, first strike, vigilance, trample, lifelink
Enchanted creature gets +4/+4 and has flying, first strike, vigilance, trample, and lifelink.

Dune-Brood Nephilim

Whenever Dune-Brood Nephilim deals combat damage to a player, create a 1/1 colorless Sand creature token for each land you control.

Bringer of the Green 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 create a 3/3 green Beast creature token.

Garth One-Eye

{T}: Choose a card name that hasn't been chosen from among Disenchant, Braingeyser, Terror, Shivan Dragon, Regrowth, and Black Lotus. Create a copy of the card with the chosen name. You may cast the copy. (You still pay its costs.)

Forest

Witch-Maw Nephilim

Whenever you cast a spell, you may put two +1/+1 counters on Witch-Maw Nephilim.
Whenever Witch-Maw Nephilim attacks, it gains trample until end of turn if its power is 10 or greater.

Mountain

Kodama's Reach

Search your library for up to two basic land cards, reveal those cards, put one onto the battlefield tapped and the other into your hand, then shuffle.

Ramos, Dragon Engine

Flying
Whenever you cast a spell, put a +1/+1 counter on Ramos, Dragon Engine for each of that spell's colors.
Remove five +1/+1 counters from Ramos: Add {W}{W}{U}{U}{B}{B}{R}{R}{G}{G}. Activate only once each turn.

Obsidian Obelisk

Obsidian Obelisk enters the battlefield tapped.
{T}: Add {C}.
{T}: Add one mana of any color. Spend this mana only to cast a multicolored spell.

Channel the Suns

Door to Nothingness

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

Command Tower

{T}: Add one mana of any color in your commander's color identity.

Swamp

O-Kagachi Made Manifest

O-Kagachi Made Manifest is all colors.
Flying, trample
Whenever O-Kagachi Made Manifest attacks, defending player chooses a nonland card in your graveyard. Return that card to your hand. O-Kagachi Made Manifest gets +X/+0 until end of turn, where X is the mana value of that card.

The Kami War

(As this Saga enters and after your draw step, add a lore counter.)
I — Exile target nonland permanent an opponent controls.
II — Return up to one other target nonland permanent to its owner's hand. Then each opponent discards a card.
III — Exile this Saga, then return it to the battlefield transformed under your control.

The Kami War // O-Kagachi Made Manifest

Unite the Coalition

Choose five. You may choose the same mode more than once.
• Target permanent phases out.
• Target player draws a card.
• Exile target player's graveyard.
• Unite the Coalition deals 2 damage to any target.
• Destroy target artifact or enchantment.

Obelisk of Alara

{1}{W}, {T}: You gain 5 life.
{1}{U}, {T}: Draw a card, then discard a card.
{1}{B}, {T}: Target creature gets -2/-2 until end of turn.
{1}{R}, {T}: Obelisk of Alara deals 3 damage to target player or planeswalker.
{1}{G}, {T}: Target creature gets +4/+4 until end of turn.

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.

Chamber Sentry

Chamber Sentry enters the battlefield with a +1/+1 counter on it for each color of mana spent to cast it.
{X}, {T}, Remove X +1/+1 counters from Chamber Sentry: It deals X damage to any target.
{W}{U}{B}{R}{G}: Return Chamber Sentry from your graveyard to your hand.

Bringer of the Blue 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 draw two cards.

Genju of the Realm

Enchant land
{2}: Enchanted land becomes a legendary 8/12 Spirit creature with trample until end of turn. It's still a land.
When enchanted land is put into a graveyard, you may return Genju of the Realm from your graveyard to your hand.

Last Stand

Target opponent loses 2 life for each Swamp you control. Last Stand deals damage to target creature equal to the number of Mountains you control. Create a 1/1 green Saproling creature token for each Forest you control. You gain 2 life for each Plains you control. Draw a card for each Island you control, then discard that many cards.

Evolving Wilds

{T}, Sacrifice Evolving Wilds: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Bring to Light

Converge — Search your library for a creature, instant, or sorcery card with mana value less than or equal to the number of colors of mana spent to cast this spell, exile that card, then shuffle. You may cast that card without paying its mana cost.

Maelstrom Nexus

The first spell you cast each turn has cascade. (When you cast your first spell, exile cards from the top of your library until you exile a nonland card that costs less. You may cast it without paying its mana cost. Put the exiled cards on the bottom in a random order.)

Bringer of the Red 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 untap target creature and gain control of it until end of turn. That creature gains haste until end of turn.

Shard Convergence

Search your library for a Plains card, an Island card, a Swamp card, and a Mountain card. Reveal those cards, put them into your hand, then shuffle.

Kaleidostone

When Kaleidostone enters the battlefield, draw a card.
{5}, {T}, Sacrifice Kaleidostone: Add {W}{U}{B}{R}{G}.

Terramorphic Expanse

{T}, Sacrifice Terramorphic Expanse: Search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

Glint-Eye Nephilim

Whenever Glint-Eye Nephilim deals combat damage to a player, draw that many cards.
{1}, Discard a card: Glint-Eye Nephilim gets +1/+1 until end of turn.

Begin the Invasion

Search your library for up to X battle cards with different names, put them onto the battlefield, then shuffle.

Conflux

Search your library for a white card, a blue card, a black card, a red card, and a green card. Reveal those cards, put them into your hand, then shuffle.

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.

Jenson Carthalion, Druid Exile

Whenever you cast a multicolored spell, scry 1. If that spell was all colors, create a 4/4 white Angel creature token with flying and vigilance.
{5}, {T}: Add {W}{U}{B}{R}{G}.

Tome of the Guildpact

Whenever you cast a multicolored spell, draw a card.
{T}: Add one mana of any color.

Allied Strategies

Domain — Target player draws a card for each basic land type among lands they control.

Awaken the Maelstrom

Awaken the Maelstrom is all colors.
Target player draws two cards. You may put an artifact card from your hand onto the battlefield. Create a token that's a copy of a permanent you control. Distribute three +1/+1 counters among one, two, or three creatures you control. Destroy target permanent an opponent controls.

Invasion of Alara

When Invasion of Alara enters the battlefield, exile cards from the top of your library until you exile two nonland cards with mana value 4 or less. You may cast one of those two cards without paying its mana cost. Put one of them into your hand. Then put the other cards exiled this way on the bottom of your library in a random order.

Invasion of Alara // Awaken the Maelstrom

Two-Headed Hellkite

Flying, menace, haste
Whenever Two-Headed Hellkite attacks, draw two cards.

Paragon of the Amesha

First strike
{W}{U}{B}{R}{G}: Until end of turn, Paragon of the Amesha becomes an Angel, gets +3/+3, and gains flying and lifelink.

Bringer of the White 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 return target artifact card from your graveyard to the battlefield.

Cascading Cataracts

Indestructible
{T}: Add {C}.
{5}, {T}: Add five mana in any combination of colors.

Prism Array

Converge — Prism Array enters the battlefield with a crystal counter on it for each color of mana spent to cast it.
Remove a crystal counter from Prism Array: Tap target creature.
{W}{U}{B}{R}{G}: Scry 3. (Look at the top three cards of your library, then put any number of them on the bottom of your library and the rest on top in any order.)

Yore-Tiller Nephilim

Whenever Yore-Tiller Nephilim attacks, return target creature card from your graveyard to the battlefield tapped and attacking.

Dragonsoul Knight

First strike
{W}{U}{B}{R}{G}: Until end of turn, Dragonsoul Knight becomes a Dragon, gets +5/+3, and gains flying and trample.

Child of Alara

Trample
When Child of Alara dies, destroy all nonland permanents. They can't be regenerated.

Harrow

As an additional cost to cast this spell, sacrifice a land.
Search your library for up to two basic land cards, put them onto the battlefield, then shuffle.

Kyodai, Soul of Kamigawa

Flash
Flying
When Kyodai, Soul of Kamigawa enters the battlefield, another target permanent gains indestructible for as long as you control Kyodai.
{W}{U}{B}{R}{G}: Kyodai gets +5/+5 until end of turn.

Omnath, Locus of All

If you would lose unspent mana, that mana becomes black instead.
At the beginning of your precombat main phase, look at the top card of your library. You may reveal that card if it has three or more colored mana symbols in its mana cost. If you do, add three mana in any combination of its colors and put it into your hand. If you don't reveal it, put it into your hand.

All Suns' Dawn

For each color, return up to one target card of that color from your graveyard to your hand. Exile All Suns' Dawn.

Widespread Thieving

Hideaway 5 (When this enchantment enters the battlefield, look at the top five cards of your library, exile one face down, then put the rest on the bottom in a random order.)
Whenever you cast a multicolored spell, create a Treasure token. Then you may pay {W}{U}{B}{R}{G}. If you do, you may play the exiled card without paying its mana cost.

Roiling Regrowth

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.

Iridian Maelstrom

Destroy each creature that isn't all colors.

Courier's Briefcase

When Courier's Briefcase enters the battlefield, create a 1/1 green and white Citizen creature token.
{T}, Sacrifice Courier's Briefcase: Add one mana of any color.
{W}{U}{B}{R}{G}, {T}, Sacrifice Courier's Briefcase: Draw three cards.

Pillar of the Paruns

{T}: Add one mana of any color. Spend this mana only to cast a multicolored spell.

Legacy Weapon

{W}{U}{B}{R}{G}: Exile target permanent.
If Legacy Weapon would be put into a graveyard from anywhere, reveal Legacy Weapon and shuffle it into its owner's library instead.

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.

Farseek

Search your library for a Plains, Island, Swamp, or Mountain card, put it onto the battlefield tapped, then shuffle.

Etched Monstrosity

Etched Monstrosity enters the battlefield with five -1/-1 counters on it.
{W}{U}{B}{R}{G}, Remove five -1/-1 counters from Etched Monstrosity: Target player draws three cards.

Crystal Quarry

{T}: Add {C}.
{5}, {T}: Add {W}{U}{B}{R}{G}.

Worldheart Phoenix

Flying
You may cast Worldheart Phoenix from your graveyard by paying {W}{U}{B}{R}{G} rather than paying its mana cost. If you do, it enters the battlefield with two +1/+1 counters on it.

The World Tree

The World Tree enters the battlefield tapped.
{T}: Add {G}.
As long as you control six or more lands, lands you control have "{T}: Add one mana of any color."
{W}{W}{U}{U}{B}{B}{R}{R}{G}{G}, {T}, Sacrifice The World Tree: Search your library for any number of God cards, put them onto the battlefield, then shuffle.

Composite Golem

Sacrifice Composite Golem: Add {W}{U}{B}{R}{G}.

Island

Timeless Lotus

Timeless Lotus enters the battlefield tapped.
{T}: Add {W}{U}{B}{R}{G}.

Prismatic Omen

Lands you control are every basic land type in addition to their other types.

Fleshformer

{W}{U}{B}{R}{G}: Fleshformer gets +2/+2 and gains fear until end of turn. Target creature gets -2/-2 until end of turn. Activate only during your turn. (A creature with fear can't be blocked except by artifact creatures and/or black creatures.)

Cultivate

Mana Cannons

Whenever you cast a multicolored spell, Mana Cannons deals X damage to any target, where X is the number of colors that spell is.

Path to the World Tree

When Path to the World Tree enters the battlefield, search your library for a basic land card, reveal it, put it into your hand, then shuffle.
{2}{W}{U}{B}{R}{G}, Sacrifice Path to the World Tree: You gain 2 life and draw two cards. Target opponent loses 2 life. Path to the World Tree deals 2 damage to up to one target creature. You create a 2/2 green Bear creature token.

Entish Restoration

Sacrifice a land. Search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle. If you control a creature with power 4 or greater, instead search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Fusion Elemental

O-Kagachi, Vengeful Kami

Flying, trample
Whenever O-Kagachi, Vengeful Kami deals combat damage to a player, if that player attacked you during their last turn, exile target nonland permanent that player controls.

Prismatic Geoscope

Prismatic Geoscope enters the battlefield tapped.
Domain — {T}: Add X mana in any combination of colors, where X is the number of basic land types among lands you control.

Exotic Orchard

{T}: Add one mana of any color that a land an opponent controls could produce.

Ink-Treader Nephilim

Whenever a player casts an instant or sorcery spell, if that spell targets only Ink-Treader Nephilim, copy the spell for each other creature that spell could target. Each copy targets a different one of those creatures.

Jegantha, the Wellspring

Companion — No card in your starting deck has more than one of the same mana symbol in its mana cost. (If this card is your chosen companion, you may put it into your hand from outside the game for {3} as a sorcery.)
{T}: Add {W}{U}{B}{R}{G}. This mana can't be spent to pay generic mana costs.