Cloud Key

As this artifact enters, choose artifact, creature, enchantment, instant, or sorcery.
Spells you cast of the chosen type cost {1} less to cast.

Mana Breach

Whenever a player casts a spell, that player returns a land they control to its owner's hand.

Heroic Intervention

Permanents you control gain hexproof and indestructible until end of turn.

Ashling the Pilgrim

{1}{R}: Put a +1/+1 counter on Ashling. If this is the third time this ability has resolved this turn, remove all +1/+1 counters from Ashling, and it deals that much damage to each creature and each player.

Sylvan Library

At the beginning of your draw step, you may draw two additional cards. If you do, choose two cards in your hand drawn this turn. For each of those cards, pay 4 life or put the card on top of your library.

Root Maze

Sylvan Tutor

Search your library for a creature card, reveal it, then shuffle and put that card on top.

Satyr Enchanter

Whenever you cast an enchantment spell, draw a card.

Rest in Peace

When this enchantment enters, exile all graveyards.
If a card or token would be put into a graveyard from anywhere, exile it instead.

Greater Auramancy

Other enchantments you control have shroud. (A permanent with shroud can't be the target of spells or abilities.)
Enchanted creatures you control have shroud.

Creepy Doll

Indestructible
Whenever this creature deals combat damage to a creature, flip a coin. If you win the flip, destroy that creature.

Elvish Spirit Guide

Exile this creature from your hand: Add {G}.

Bountiful Promenade

This land enters tapped unless you have two or more opponents.
{T}: Add {G} or {W}.

Mirri's Guile

At the beginning of your upkeep, you may look at the top three cards of your library, then put them back in any order.

Ashes of the Abhorrent

Players can't cast spells from graveyards or activate abilities of cards in graveyards.
Whenever a creature dies, you gain 1 life.

Oboro, Palace in the Clouds

{T}: Add {U}.
{1}: Return Oboro to its owner's hand.

Ground Seal

When this enchantment enters, draw a card.
Cards in graveyards can't be the targets of spells or abilities.

Neheb, the Eternal

Afflict 3 (Whenever this creature becomes blocked, defending player loses 3 life.)
At the beginning of each of your postcombat main phases, add {R} for each 1 life your opponents have lost this turn.

Exploration

You may play an additional land on each of your turns.

Sword of Hours

Whenever equipped creature attacks, put a +1/+1 counter on it.
Whenever equipped creature deals combat damage, roll a d12. If the result is greater than the damage dealt or the result is 12, double the number of +1/+1 counters on that creature.
Equip {2} ({2}: Attach to target creature you control. Equip only as a sorcery.)

Wooded Bastion

{T}: Add {C}.
{G/W}, {T}: Add {G}{G}, {G}{W}, or {W}{W}.

Argothian Enchantress

Shroud (This creature can't be the target of spells or abilities.)
Whenever you cast an enchantment spell, draw a card.

Jhoira's Familiar

Flying
Historic spells you cast cost {1} less to cast. (Artifacts, legendaries, and Sagas are historic.)

Overgrown Farmland

This land enters tapped unless you control two or more other lands.
{T}: Add {G} or {W}.

Darksteel Mutation

Enchant creature
Enchanted creature is an Insect artifact creature with base power and toughness 0/1 and has indestructible, and it loses all other abilities, card types, and creature types.

Hall of Heliod's Generosity

{T}: Add {C}.
{1}{W}, {T}: Put target enchantment card from your graveyard on top of your library.

Sensei's Divining Top

{1}: Look at the top three cards of your library, then put them back in any order.
{T}: Draw a card, then put this artifact on top of its owner's library.

Worldly Tutor

Search your library for a creature card, reveal it, then shuffle and put the card on top.

Burgeoning

Whenever an opponent plays a land, you may put a land card from your hand onto the battlefield.

Gratuitous Violence

If a creature you control would deal damage to a permanent or player, it deals double that damage instead.