Astral Cornucopia enters the battlefield with X charge counters on it. {T}: Choose a color. Add one mana of that color for each charge counter on Astral Cornucopia.

When Contagion Engine enters the battlefield, put a -1/-1 counter on each creature target player controls. {4}, {T}: Proliferate, then proliferate again. (Choose any number of permanents and/or players, then give each another counter of each kind already there. Then do it again.)

Multikicker {2} (You may pay an additional {2} any number of times as you cast this spell.) Everflowing Chalice enters the battlefield with a charge counter on it for each time it was kicked. {T}: Add {C} for each charge counter on Everflowing Chalice.

Nevinyrral's Disk enters the battlefield tapped. {1}, {T}: Destroy all artifacts, creatures, and enchantments.

Whenever you activate an ability, if it isn't a mana ability, you may pay {2}. If you do, copy that ability. You may choose new targets for the copy.

{1}, {T}: Add {G}{U}.

{T}: Add {C}{C}.

Partner with Toothy, Imaginary Friend (When this creature enters the battlefield, target player may put Toothy into their hand from their library, then shuffle.) If one or more counters would be put on a permanent your team controls, that many plus one of each of those kinds of counters are put on that permanent instead.

Whenever you draw a card, put a +1/+1 counter on Chasm Skulker. When Chasm Skulker dies, create X 1/1 blue Squid creature tokens with islandwalk, where X is the number of +1/+1 counters on Chasm Skulker. (They can't be blocked as long as defending player controls an Island.)

When Deepglow Skate enters the battlefield, double the number of each kind of counter on any number of target permanents.

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

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

Defender, flying Prevent all combat damage that would be dealt to and dealt by Fog Bank.

Whenever a player casts a spell, you may put a +1/+1 counter on Forgotten Ancient. At the beginning of your upkeep, you may move any number of +1/+1 counters from Forgotten Ancient onto other creatures.

Defender, flying Prevent all combat damage that would be dealt to Guard Gomazoa.

Defender (This creature can't attack.) Whenever Hornet Nest is dealt damage, create that many 1/1 green Insect creature tokens with flying and deathtouch. (Any amount of damage a creature with deathtouch deals to a creature is enough to destroy it.)

Level up {U} ({U}: Put a level counter on this. Level up only as a sorcery.) LEVEL 4-6 2/4 LEVEL 7+ 3/5 At the beginning of each end step, if it's not your turn, take an extra turn after this one.

Trample Whenever a player casts a spell, put a +1/+1 counter on Managorger Hydra.

Sacrifice Sakura-Tribe Elder: Search your library for a basic land card, put that card onto the battlefield tapped, then shuffle.

Spike Weaver enters the battlefield with three +1/+1 counters on it. {2}, Remove a +1/+1 counter from Spike Weaver: Put a +1/+1 counter on target creature. {1}, Remove a +1/+1 counter from Spike Weaver: Prevent all combat damage that would be dealt this turn.

Trample If damage would be dealt to another creature you control, prevent that damage. Put a +1/+1 counter on that creature for each 1 damage prevented this way. When Vigor is put into a graveyard from anywhere, shuffle it into its owner's library.

Flying Infect (This creature deals damage to creatures in the form of -1/-1 counters and to players in the form of poison counters.) {3}{U}: Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

If an effect would create one or more tokens under your control, it creates twice that many of those tokens instead. If an effect would put one or more counters on a permanent you control, it puts twice that many of those counters on that permanent instead.

Whenever you cast a spell, proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Whenever an opponent casts a spell, you may draw a card unless that player pays {1}.

Create X 1/2 green Spider creature tokens with reach, where X is the number of creatures attacking you. Prevent all combat damage that would be dealt this turn by non-Spider creatures.

Destroy target permanent. Its controller creates a 3/3 green Beast creature token.

Return target nonland permanent you don't control to its owner's hand. Overload {6}{U} (You may cast this spell for its overload cost. If you do, change "target" in its text to "each.")

Return all creatures to their owners' hands.

{T}: Add {C}. Basic landcycling {1} ({1}, Discard this card: Search your library for a basic land card, reveal it, put it into your hand, then shuffle.)

({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.

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

({T}: Add {G}.)

{T}: Add {C}. {T}: Choose target commander that entered the battlefield this turn. Put a +1/+1 counter on it if it's a creature and a loyalty counter on it if it's a planeswalker.

({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}.

Lumbering Falls enters the battlefield tapped. {T}: Add {G} or {U}. {2}{G}{U}: Lumbering Falls becomes a 3/3 green and blue Elemental creature with hexproof until end of turn. It's still a land.

{T}: Add {C}. {1}, {T}: Put a storage counter on Mage-Ring Network. {T}, Remove any number of storage counters from Mage-Ring Network: Add {C} for each storage counter removed this way.

{T}: Untap target attacking creature. Prevent all combat damage that would be dealt to and dealt by that creature this turn.

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.

Path of Ancestry enters the battlefield tapped. {T}: Add one mana of any color in your commander's color identity. When that mana is spent to cast a creature spell that shares a creature type with your commander, scry 1. (Look at the top card of your library. You may put that card on the bottom.)

Simic Growth Chamber enters the battlefield tapped. When Simic Growth Chamber enters the battlefield, return a land you control to its owner's hand. {T}: Add {G}{U}.

+2: Create a 1/1 green Elf Druid creature token with "{T}: Add {G}." −2: Destroy target artifact or enchantment. −6: Draw a card for each green creature you control. Freyalise, Llanowar's Fury can be your commander.

+1: Untap two target lands. −1: Create a 3/3 green Beast creature token. −4: Creatures you control get +3/+3 and gain trample until end of turn.

+1: Create a 3/3 green Beast creature token. −3: Draw cards equal to the greatest power among creatures you control. −6: Create a 6/6 green Wurm creature token for each land you control.

+2: Each player draws a card. −1: Target player draws a card. −10: Target player mills twenty cards.

+1: Until your next turn, whenever a creature an opponent controls attacks, it gets -1/-0 until end of turn. −2: Reveal the top three cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other on the bottom of your library in any order. −8: For each player, search that player's library for a nonland card and exile it, then that player shuffles. You may cast those cards without paying their mana costs.

+1: Draw a card. +1: Untap all creatures you control. −9: Gain control of up to three target creatures.

+1: Draw a card. Target player mills a card. 0: Target player mills ten cards. −7: Any number of target players each draw twenty cards.

+1: Look at the top two cards of your library. Put one of them into your graveyard. −3: Return another target nonland permanent to its owner's hand. −8: Each player shuffles their hand and graveyard into their library. You draw seven cards.

+2: Look at the top card of target player's library. You may put that card on the bottom of that player's library. 0: Draw three cards, then put two cards from your hand on top of your library in any order. −1: Return target creature to its owner's hand. −12: Exile all cards from target player's library, then that player shuffles their hand into their library.

+1: Scry 1, then draw a card. −2: Return target creature to its owner's hand. −8: You get an emblem with "Whenever an opponent casts their first spell each turn, counter that spell."

+4: Target player exiles a card from their hand. −3: Exile target permanent. −14: Restart the game, leaving in exile all non-Aura permanent cards exiled with Karn Liberated. Then put those cards onto the battlefield under your control.

+1: Untap up to one target creature and up to one target land. −2: Reveal the top four cards of your library. You may put a creature card and/or a land card from among them into your hand. Put the rest into your graveyard. −8: You get an emblem with "Whenever a creature enters the battlefield under your control, you may have it fight target creature." Then create three 8/8 blue Octopus creature tokens.

+1: Until your next turn, prevent all damage that would be dealt to and dealt by target permanent an opponent controls. −1: Draw a card. You may play an additional land this turn. −5: You get an emblem with "At the beginning of your end step, create a 9/9 blue Kraken creature token."

+1: Untap target land you control. Until your next turn, it becomes a 5/5 Elemental creature with haste. It's still a land. −3: Return target permanent card from your graveyard to your hand. −6: You get an emblem with "Whenever a land enters the battlefield under your control, you may draw a card."

+1: Create a 0/1 green Plant creature token. −2: Put a +1/+1 counter on each creature you control. −7: You gain X life and draw X cards, where X is the number of lands you control.

+1: Tap target permanent. It doesn't untap during its controller's next untap step. −2: Draw a card for each tapped creature target player controls. −8: You get an emblem with "You have no maximum hand size" and "Whenever a card is put into your graveyard from anywhere, you may return it to your hand."

+1: Look at the top two cards of your library. Put one of them into your hand and the other on the bottom of your library. −1: Untap up to four target permanents. −10: You get an emblem with "You may activate loyalty abilities of planeswalkers you control on any player's turn any time you could cast an instant." Teferi, Temporal Archmage can be your commander.

+1: Untap up to two target artifacts. −X: Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle. −5: Artifacts you control become artifact creatures with base power and toughness 5/5 until end of turn.

+2: Ugin, the Spirit Dragon deals 3 damage to any target. −X: Exile each permanent with mana value X or less that's one or more colors. −10: You gain 7 life, draw seven cards, then put up to seven permanent cards from your hand onto the battlefield.

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.

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

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.

Search your library for a Forest card, put that card onto the battlefield, then shuffle.

For each player, choose friend or foe. Each friend searches their library for a land card, puts it onto the battlefield tapped, then shuffles. Each foe sacrifices an artifact or enchantment they control.