You may have Auton Soldier enter the battlefield as a copy of any creature on the battlefield, except it isn't legendary, is an artifact in addition to its other types, and has myriad. (Whenever it attacks, for each opponent other than defending player, you may put a token that's a copy of this creature onto the battlefield tapped and attacking that player or a planeswalker they control. Exile the tokens at end of combat.)

Secret council — When Elrond of the White Council enters the battlefield, each player secretly votes for fellowship or aid, then those votes are revealed. For each fellowship vote, the voter chooses a creature they control. You gain control of each creature chosen this way, and they gain "This creature can't attack its owner." Then for each aid vote, put a +1/+1 counter on each creature you control.

Barren Moor enters the battlefield tapped. {T}: Add {B}. Cycling {B} ({B}, Discard this card: Draw a card.)

Bojuka Bog enters the battlefield tapped. When Bojuka Bog enters the battlefield, exile target player's graveyard. {T}: Add {B}.

({T}: Add {G} or {U}.) As Breeding Pool enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Deathcap Glade enters the battlefield tapped unless you control two or more other lands. {T}: Add {B} or {G}.

Dreamroot Cascade enters the battlefield tapped unless you control two or more other lands. {T}: Add {G} or {U}.

Drowned Catacomb enters the battlefield tapped unless you control an Island or a Swamp. {T}: Add {U} or {B}.

({T}: Add {U} or {B}.) Fetid Pools enters the battlefield tapped. Cycling {2} ({2}, Discard this card: Draw a card.)

Field of the Dead enters the battlefield tapped. {T}: Add {C}. Whenever Field of the Dead or another land enters the battlefield under your control, if you control seven or more lands with different names, create a 2/2 black Zombie creature token.

({T}: Add {G}.)

Hinterland Harbor enters the battlefield tapped unless you control a Forest or an Island. {T}: Add {G} or {U}.

({T}: Add {U}.)

Khalni Garden enters the battlefield tapped. When Khalni Garden enters the battlefield, create a 0/1 green Plant creature token. {T}: Add {G}.

Littjara Mirrorlake enters the battlefield tapped. {T}: Add {U}. {2}{G}{G}{U}, {T}, Sacrifice Littjara Mirrorlake: Create a token that's a copy of target creature you control, except it enters the battlefield with an additional +1/+1 counter on it. Activate only as a sorcery.

Lonely Sandbar enters the battlefield tapped. {T}: Add {U}. Cycling {U} ({U}, Discard this card: Draw a card.)

Morphic Pool enters the battlefield tapped unless you have two or more opponents. {T}: Add {U} or {B}.

Hideaway 4 (When this land enters the battlefield, look at the top four cards of your library, exile one face down, then put the rest on the bottom in a random order.) Mosswort Bridge enters the battlefield tapped. {T}: Add {G}. {G}, {T}: You may play the exiled card without paying its mana cost if creatures you control have total power 10 or greater.

Myriad Landscape enters the battlefield tapped. {T}: Add {C}. {2}, {T}, Sacrifice Myriad Landscape: Search your library for up to two basic land cards that share a land type, put them onto the battlefield tapped, then shuffle.

({T}: Add {B} or {G}.) As Overgrown Tomb enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Rejuvenating Springs enters the battlefield tapped unless you have two or more opponents. {T}: Add {G} or {U}.

({T}: Add {B}.)

Undergrowth Stadium enters the battlefield tapped unless you have two or more opponents. {T}: Add {B} or {G}.

Vivid Creek enters the battlefield tapped with two charge counters on it. {T}: Add {U}. {T}, Remove a charge counter from Vivid Creek: Add one mana of any color.

Vivid Grove enters the battlefield tapped with two charge counters on it. {T}: Add {G}. {T}, Remove a charge counter from Vivid Grove: Add one mana of any color.

Vivid Marsh enters the battlefield tapped with two charge counters on it. {T}: Add {B}. {T}, Remove a charge counter from Vivid Marsh: Add one mana of any color.

({T}: Add {U} or {B}.) As Watery Grave enters the battlefield, you may pay 2 life. If you don't, it enters the battlefield tapped.

Woodland Cemetery enters the battlefield tapped unless you control a Swamp or a Forest. {T}: Add {B} or {G}.

When Avenger of Zendikar enters the battlefield, create a 0/1 green Plant creature token for each land you control. Landfall — Whenever a land enters the battlefield under your control, you may put a +1/+1 counter on each Plant creature you control.

Creatures with power less than Champion of Lambholt's power can't block creatures you control. Whenever another creature enters the battlefield under your control, put a +1/+1 counter on Champion of Lambholt.

When Cyclone Summoner enters the battlefield, if you cast it from your hand, return all permanents to their owners' hands except for Giants, Wizards, and lands.

Vanishing 3 (This creature enters the battlefield with three time counters on it. At the beginning of your upkeep, remove a time counter from it. When the last is removed, sacrifice it.) When Deep Forest Hermit enters the battlefield, create four 1/1 green Squirrel creature tokens. Squirrels you control get +1/+1.

Flying Whenever a nontoken creature enters the battlefield under an opponent's control, create a token that's a copy of that creature except it's an artifact in addition to its other types. Then exile all other tokens created with Faerie Artisans.

Deathtouch Whenever Grave Titan enters the battlefield or attacks, create two 2/2 black Zombie creature tokens.

Flying, deathtouch When Hornet Queen enters the battlefield, create four 1/1 green Insect creature tokens with flying and deathtouch.

When Phyrexian Delver enters the battlefield, return target creature card from your graveyard to the battlefield. You lose life equal to that card's mana value.

Flying When Puppeteer Clique enters the battlefield, put target creature card from an opponent's graveyard onto the battlefield under your control. It gains haste. At the beginning of your next end step, exile it. Persist (When this creature dies, if it had no -1/-1 counters on it, return it to the battlefield under its owner's control with a -1/-1 counter on it.)

Flying, deathtouch When Baleful Strix enters the battlefield, draw a card.

Flying Whenever Cemetery Illuminator enters the battlefield or attacks, exile a card from a graveyard. You may look at the top card of your library any time. Once each turn, you may cast a spell from the top of your library if it shares a card type with a card exiled with Cemetery Illuminator.

When Champion of Wits enters the battlefield, you may draw cards equal to its power. If you do, discard two cards. Eternalize {5}{U}{U} ({5}{U}{U}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Naga Wizard with no mana cost. Eternalize only as a sorcery.)

Flying When Cloudkin Seer enters the battlefield, draw a card.

When Coiling Oracle enters the battlefield, reveal the top card of your library. If it's a land card, put it onto the battlefield. Otherwise, put that card into your hand.

Flying When Diluvian Primordial enters the battlefield, for each opponent, you may cast up to one target instant or sorcery card from that player's graveyard without paying its mana cost. If a spell cast this way would be put into a graveyard, exile it instead.

When Elvish Visionary enters the battlefield, draw a card.

When Eternal Witness enters the battlefield, you may return target card from your graveyard to your hand.

When Fierce Empath enters the battlefield, you may search your library for a creature card with mana value 6 or greater, reveal it, put it into your hand, then shuffle.

When Gravedigger enters the battlefield, you may return target creature card from your graveyard to your hand.

Whenever another nontoken creature enters the battlefield under your control, investigate. {T}, Sacrifice X Clues: Target opponent reveals the top X cards of their library. You may put a nonland permanent card with mana value X or less from among them onto the battlefield under your control. That player puts the rest on the bottom of their library in a random order.

Flying When Mulldrifter enters the battlefield, draw two cards. Evoke {2}{U} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

Whenever Risen Reef or another Elemental enters the battlefield under your control, look at the top card of your library. If it's a land card, you may put it onto the battlefield tapped. If you don't put the card onto the battlefield, put it into your hand.

Deathtouch Exploit (When this creature enters the battlefield, you may sacrifice a creature.) When Sidisi, Undead Vizier exploits a creature, you may search your library for a card, put it into your hand, then shuffle.

Trample Whenever another nontoken creature enters the battlefield under your control, you may draw a card.

When Timeless Witness enters the battlefield, return target card from your graveyard to your hand. Eternalize {5}{G}{G} ({5}{G}{G}, Exile this card from your graveyard: Create a token that's a copy of it, except it's a 4/4 black Zombie Human Shaman with no mana cost. Eternalize only as a sorcery.)

Defender When Wall of Blossoms enters the battlefield, draw a card.

Whenever another nontoken creature enters the battlefield, you may pay {1}{G}. If you do, that creature's controller creates a token that's a copy of that creature.

Soulbond (You may pair this creature with another unpaired creature when either enters the battlefield. They remain paired for as long as you control both of them.) As long as Deadeye Navigator is paired with another creature, each of those creatures has "{1}{U}: Exile this creature, then return it to the battlefield under your control."

Fiend Artisan gets +1/+1 for each creature card in your graveyard. {X}{B/G}, {T}, Sacrifice another creature: Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle. Activate only as a sorcery.

When Man-o'-War enters the battlefield, return target creature to its owner's hand.

Flying Whenever another nontoken creature you control dies, you may exile it. If you do, create a token that's a copy of that creature, except it's 1/1 and it's a Nightmare in addition to its other types.

{T}, Sacrifice another creature: Search your library for a creature card with mana value equal to 1 plus the sacrificed creature's mana value, put that card onto the battlefield, then shuffle. Activate only as a sorcery.

You may have Progenitor Mimic enter the battlefield as a copy of any creature on the battlefield, except it has "At the beginning of your upkeep, if this creature isn't a token, create a token that's a copy of this creature."

Flash When Venser, Shaper Savant enters the battlefield, return target spell or permanent to its owner's hand.

When Bane of Progress enters the battlefield, destroy all artifacts and enchantments. Put a +1/+1 counter on Bane of Progress for each permanent destroyed this way.

Flying When Deathbringer Regent enters the battlefield, if you cast it from your hand and there are five or more other creatures on the battlefield, destroy all other creatures.

When Hostage Taker enters the battlefield, exile another target creature or artifact until Hostage Taker leaves the battlefield. You may cast that card for as long as it remains exiled, and mana of any type can be spent to cast that spell.

When Kogla, the Titan Ape enters the battlefield, it fights up to one target creature you don't control. Whenever Kogla attacks, destroy target artifact or enchantment defending player controls. {1}{G}: Return target Human you control to its owner's hand. Kogla gains indestructible until end of turn.

Changeling (This card is every creature type.) When Masked Vandal enters the battlefield, you may exile a creature card from your graveyard. If you do, exile target artifact or enchantment an opponent controls.

When Ravenous Chupacabra enters the battlefield, destroy target creature an opponent controls.

When Reclamation Sage enters the battlefield, you may destroy target artifact or enchantment.

Fear (This creature can't be blocked except by artifact creatures and/or black creatures.) When Shriekmaw enters the battlefield, destroy target nonartifact, nonblack creature. Evoke {1}{B} (You may cast this spell for its evoke cost. If you do, it's sacrificed when it enters the battlefield.)

When Terastodon enters the battlefield, you may destroy up to three target noncreature permanents. For each permanent put into a graveyard this way, its controller creates a 3/3 green Elephant creature token.

Flying {T}: Add one mana of any color.

Vigilance Whenever Cemetery Prowler enters the battlefield or attacks, exile a card from a graveyard. Spells you cast cost {1} less to cast for each card type they share with cards exiled with Cemetery Prowler.

{T}: Add {G}.

When Farhaven Elf enters the battlefield, you may search your library for a basic land card, put it onto the battlefield tapped, then shuffle.

{T}: Add {G}.

Reach Whenever another permanent enters the battlefield under your control, if it wasn't put onto the battlefield with this ability, you may put a permanent card with equal or lesser mana value from your hand onto the battlefield. Partner (You can have two commanders if both have partner.)

Landfall — Whenever a land enters the battlefield under your control, add one mana of any color.

When Rishkar, Peema Renegade enters the battlefield, put a +1/+1 counter on each of up to two target creatures. Each creature you control with a counter on it has "{T}: Add {G}."

When Springbloom Druid enters the battlefield, you may sacrifice a land. If you do, search your library for up to two basic land cards, put them onto the battlefield tapped, then shuffle.