Feeding Grounds

Red spells cost {1} less to cast.
Green spells cost {1} less to cast.
Whenever chaos ensues, put X +1/+1 counters on target creature, where X is that creature's mana value.

Enigma Ridges

When you planeswalk to Enigma Ridges, each player who controls fewer lands than the player who controls the most lands searches their library for a number of basic land cards less than or equal to the difference, reveals them, puts them into their hand, then shuffles.
Whenever chaos ensues, draw a card, then you may put a land card from your hand onto the battlefield.

The Dark Barony

Whenever a nonblack card is put into a player's graveyard from anywhere, that player loses 1 life.
Whenever chaos ensues, each opponent discards a card.

Krosa

All creatures get +2/+2.
Whenever chaos ensues, you may add {W}{U}{B}{R}{G}.

Izzet Steam Maze

Whenever a player casts an instant or sorcery spell, that player copies it. The player may choose new targets for the copy.
Whenever chaos ensues, instant and sorcery spells you cast this turn cost {3} less to cast.

Panopticon

When you planeswalk to Panopticon, draw a card.
At the beginning of your draw step, draw an additional card.
Whenever chaos ensues, draw a card.

The Great Forest

Each creature assigns combat damage equal to its toughness rather than its power.
Whenever chaos ensues, creatures you control get +0/+2 and gain trample until end of turn.

Selesnya Loft Gardens

If an effect would create one or more tokens, it creates twice that many of those tokens instead.
If an effect would put one or more counters on a permanent, it puts twice that many of those counters on that permanent instead.
Whenever chaos ensues, until end of turn, whenever you tap a land for mana, add one mana of any type that land produced.

Velis Vel

Each creature gets +1/+1 for each other creature on the battlefield that shares at least one creature type with it. (For example, if two Elemental Shamans and an Elemental Spirit are on the battlefield, each gets +2/+2.)
Whenever chaos ensues, target creature gains all creature types until end of turn.

Minamo

Whenever a player casts a spell, that player may draw a card.
Whenever chaos ensues, each player may return a blue card from their graveyard to their hand.

Astral Arena

No more than one creature can attack each combat.
No more than one creature can block each combat.
Whenever chaos ensues, Astral Arena deals 2 damage to each creature.

Onakke Catacomb

All creatures are black and have deathtouch.
Whenever chaos ensues, creatures you control get +1/+0 and gain first strike until end of turn.

The Fourth Sphere

At the beginning of your upkeep, sacrifice a nonblack creature.
Whenever chaos ensues, create a 2/2 black Zombie creature token.

Akoum

Players may cast enchantment spells as though they had flash.
Whenever chaos ensues, destroy target creature that isn't enchanted.

Ten Wizards Mountain

Whenever you roll the planar die, put a +1/+1 counter on up to one target creature.
Whenever chaos ensues, creatures you control gain flying until end of turn.

Prahv

If you cast a spell this turn, you can't attack with creatures.
If you attacked with creatures this turn, you can't cast spells.
Whenever chaos ensues, you gain life equal to the number of cards in your hand.

Turri Island

Creature spells cost {2} less to cast.
Whenever chaos ensues, reveal the top three cards of your library. Put all creature cards revealed this way into your hand and the rest into your graveyard.

Hedron Fields of Agadeem

Creatures with power 7 or greater can't attack or block.
Whenever chaos ensues, create a 7/7 colorless Eldrazi creature token with annihilator 1. (Whenever it attacks, defending player sacrifices a permanent of their choice.)

Stairs to Infinity

Players have no maximum hand size.
Whenever you roll the planar die, draw a card.
Whenever chaos ensues, reveal the top card of your planar deck. You may put it on the bottom of your planar deck.

Llanowar

All creatures have "{T}: Add {G}{G}."
Whenever chaos ensues, untap all creatures you control.

Megaflora Jungle

Each creature with mana value 2 or less gets +2/+2.
Whenever chaos ensues, create a 1/1 green Insect creature token with flying named Butterfly.

Tember City

Whenever a player taps a land for mana, Tember City deals 1 damage to that player.
Whenever chaos ensues, each other player sacrifices a nonland permanent of their choice.

Quicksilver Sea

When you planeswalk to Quicksilver Sea and at the beginning of your upkeep, scry 4. (Look at the top four cards of your library, then put any number of them on the bottom and the rest on top in any order.)
Whenever chaos ensues, reveal the top card of your library. You may play it without paying its mana cost.

The Eon Fog

Players skip their untap steps.
Whenever chaos ensues, untap all permanents you control.

Sea of Sand

Players reveal each card they draw.
Whenever a player draws a land card, that player gains 3 life.
Whenever a player draws a nonland card, that player loses 3 life.
Whenever chaos ensues, put target permanent on top of its owner's library.

Orzhova

When you planeswalk away from Orzhova, each player returns all creature cards from their graveyard to the battlefield.
Whenever chaos ensues, for each opponent, exile up to one target creature card from that player's graveyard.

Sokenzan

All creatures get +1/+1 and have haste.
Whenever chaos ensues, untap all creatures that attacked this turn. If it's a main phase, there is an additional combat phase after this phase, followed by an additional main phase.

Agyrem

Whenever a white creature dies, return it to the battlefield under its owner's control at the beginning of the next end step.
Whenever a nonwhite creature dies, return it to its owner's hand at the beginning of the next end step.
Whenever chaos ensues, creatures can't attack you until a player planeswalks.

Nontoken creatures are enchantments in addition to their other types.
Constellation — Whenever an enchantment you control enters, you gain 1 life.
Whenever chaos ensues, choose a color. Add an amount of mana of that color equal to your devotion to that color.

Esper

Artifact spells cost {1} less to cast.
Whenever chaos ensues, creatures you control that are white, blue, and/or black become artifacts in addition to their other types until end of turn. Then each artifact creature you control gains vigilance, menace, and lifelink until end of turn.

Nephalia

At the beginning of your end step, mill seven cards. Then return a card at random from your graveyard to your hand.
Whenever chaos ensues, return target card from your graveyard to your hand.

Sanctum of Serra

When you planeswalk away from Sanctum of Serra, destroy all nonland permanents.
Whenever chaos ensues, you may have your life total become 20.

Isle of Vesuva

Whenever a nontoken creature enters, its controller creates a token that's a copy of that creature.
Whenever chaos ensues, destroy target creature and all other creatures with the same name as that creature.

Naya

You may play any number of lands on each of your turns.
Whenever chaos ensues, target red, green, or white creature you control gets +1/+1 until end of turn for each land you control.

Horizon Boughs

All permanents untap during each player's untap step.
Whenever chaos ensues, you may search your library for up to three basic land cards, put them onto the battlefield tapped, then shuffle.

Eloren Wilds

Whenever a player taps a permanent for mana, that player adds one mana of any type that permanent produced.
Whenever chaos ensues, target player can't cast spells until a player planeswalks.

Glen Elendra

At end of combat, you may exchange control of target creature you control that dealt combat damage to a player this combat and target creature that player controls.
Whenever chaos ensues, gain control of target creature you own.

Fields of Summer

Whenever a player casts a spell, that player may gain 2 life.
Whenever chaos ensues, you may gain 10 life.

Windriddle Palaces

Players play with the top card of their libraries revealed.
You may play lands and cast spells from the top of any player's library.
Whenever chaos ensues, each player mills a card.

Skybreen

Players play with the top card of their libraries revealed.
Spells that share a card type with the top card of a library can't be cast.
Whenever chaos ensues, target player loses life equal to the number of cards in their hand.

Takenuma

Whenever a creature leaves the battlefield, its controller draws a card.
Whenever chaos ensues, return target creature you control to its owner's hand.

Immersturm

Whenever a creature enters, that creature's controller may have it deal damage equal to its power to any target of their choice.
Whenever chaos ensues, exile target creature, then return it to the battlefield under its owner's control.

Aretopolis

When you planeswalk to Aretopolis and at the beginning of your upkeep, put a scroll counter on Aretopolis, then you gain life equal to the number of scroll counters on it.
When Aretopolis has ten or more scroll counters on it, planeswalk.
Whenever chaos ensues, put a scroll counter on Aretopolis, then draw cards equal to the number of scroll counters on it.

Otaria

Instant and sorcery cards in graveyards have flashback. The flashback cost is equal to the card's mana cost. (Its owner may cast the card from their graveyard for its mana cost. Then they exile it.)
Whenever chaos ensues, take an extra turn after this one.

Norn's Dominion

When you planeswalk away from Norn's Dominion, destroy each nonland permanent without a fate counter on it, then remove all fate counters from all permanents.
Whenever chaos ensues, you may put a fate counter on target permanent.