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."

Indestructible (Effects that say "destroy" don't destroy this artifact.) At the beginning of your upkeep, you may put a charge counter on Darksteel Reactor. When Darksteel Reactor has twenty or more charge counters on it, you win the game.

You may pay 1 life and exile a blue card from your hand rather than pay this spell's mana cost. Counter target spell.

{G}{G}: Put a spore counter on target Fungus.

Counter target spell. At the beginning of your next upkeep, pay {3}{U}{U}. If you don't, you lose the game.

Draw three cards, then put two cards from your hand on top of your library in any order.

Reveal the top five cards of your library. An opponent separates those cards into two piles. Put one pile into your hand and the other into your graveyard.

Evolve (Whenever a creature enters the battlefield under your control, if that creature has greater power or toughness than this creature, put a +1/+1 counter on this creature.) Whenever a +1/+1 counter is put on Fathom Mage, you may draw a card.

+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.

Each opponent can't draw more than one card each turn. −2: Look at the top four cards of your library. You may reveal a noncreature, nonland card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.

{T}: Put a charge counter on Otherworld Atlas. {T}: Each player draws a card for each charge counter on Otherworld Atlas.

Enchant player At the beginning of enchanted player's first upkeep each turn, that player gets an additional upkeep step after this step.

At the beginning of your upkeep, put a spore counter on Psychotrope Thallid. Remove three spore counters from Psychotrope Thallid: Create a 1/1 green Saproling creature token. {1}, Sacrifice a Saproling: Draw a card.

Draw cards equal to the greatest power among creatures you control. You may cast a spell with mana value 5 or less from your hand without paying its mana cost.

Whenever a creature enters the battlefield under your control, scry 1. (Look at the top card of your library. You may put that card on the bottom of your library.) Whenever you cast a spell that targets a creature you control, draw a card.

{T}: Add {C}. {G}{U}, {T}: You may cast spells this turn as though they had flash.

({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 {C}. {G/U}, {T}: Add {G}{G}, {G}{U}, or {U}{U}.

({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}.)

{T}, Pay 1 life, Sacrifice Misty Rainforest: Search your library for a Forest or Island card, put it onto the battlefield, then shuffle.

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

{2}{G/U}, {Q}: Double the number of each kind of counter on target permanent. ({Q} is the untap symbol.)

Creatures you control have hexproof. {1}{G}: Regenerate target creature. (The next time it would be destroyed, instead tap it, remove it from combat, and heal all damage on it.)

If Leyline of Anticipation is in your opening hand, you may begin the game with it on the battlefield. You may cast spells as though they had flash.

Equipped creature has haste and shroud. (It can't be the target of spells or abilities.) Equip {0}

At the beginning of your upkeep, put a spore counter on Savage Thallid. Remove three spore counters from Savage Thallid: Create a 1/1 green Saproling creature token. Sacrifice a Saproling: Regenerate target Fungus.

Choose one — • Target creature gets +3/+3 until end of turn. • Permanents you control gain hexproof until end of turn. • Return target creature to its owner's hand.

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

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.

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.

{2}: Put a charge counter on Gemstone Array. Remove a charge counter from Gemstone Array: Add one mana of any color.

{T}: Add an amount of {G} equal to your devotion to green. (Each {G} in the mana costs of permanents you control counts toward your devotion to green.)

Untap all permanents you control during each other player's untap step.

Sphere of the Suns enters the battlefield tapped and with three charge counters on it. {T}, Remove a charge counter from Sphere of the Suns: Add one mana of any color.

At the beginning of your upkeep, put a spore counter on Utopia Mycon. Remove three spore counters from Utopia Mycon: Create a 1/1 green Saproling creature token. Sacrifice a Saproling: Add one mana of any color.

Choose two — • Counter target spell. • Return target permanent to its owner's hand. • Tap all creatures your opponents control. • Draw a card.

As an additional cost to cast this spell, return a land you control to its owner's hand. Counter target spell.

Copy target instant or sorcery spell, then return it to its owner's hand. You may choose new targets for the copy.

At the beginning of your upkeep, put a spore counter on Elvish Farmer. Remove three spore counters from Elvish Farmer: Create a 1/1 green Saproling creature token. Sacrifice a Saproling: You gain 2 life.

At the beginning of your upkeep, put a spore counter on Thallid Devourer. Remove three spore counters from Thallid Devourer: Create a 1/1 green Saproling creature token. Sacrifice a Saproling: Thallid Devourer gets +1/+2 until end of turn.

At the beginning of your upkeep, put a spore counter on Thallid Germinator. Remove three spore counters from Thallid Germinator: Create a 1/1 green Saproling creature token. Sacrifice a Saproling: Target creature gets +1/+1 until end of turn.

At the beginning of your upkeep, put a spore counter on each Fungus you control. Remove three spore counters from Sporesower Thallid: Create a 1/1 green Saproling creature token.

At the beginning of your upkeep, put a spore counter on Sporoloth Ancient. Creatures you control have "Remove two spore counters from this creature: Create a 1/1 green Saproling creature token."

Ascend (If you control ten or more permanents, you get the city's blessing for the rest of the game.) At the beginning of each upkeep, create a 1/1 green Saproling creature token. Saprolings you control get +2/+2 as long as you have the city's blessing.

At the beginning of your upkeep, put a spore counter on Thallid. Remove three spore counters from Thallid: Create a 1/1 green Saproling creature token.

Defender At the beginning of your upkeep, put a spore counter on Thallid Shell-Dweller. Remove three spore counters from Thallid Shell-Dweller: Create a 1/1 green Saproling creature token.

Convoke (Your creatures can help cast this spell. Each creature you tap while casting this spell pays for {1} or one mana of that creature's color.) Search your library for a creature card with mana value X or less, put it onto the battlefield, then shuffle.

Search your library for an artifact card, reveal it, put it into your hand, then shuffle.

{G}, {T}, Discard a creature card: Search your library for a creature card, reveal it, put it into your hand, then shuffle.

Choose two — • Target player gains 7 life. • Put target noncreature permanent on top of its owner's library. • Target player shuffles their graveyard into their library. • Search your library for a creature card, reveal it, put it into your hand, then shuffle.

+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.

When Tribute Mage enters the battlefield, you may search your library for an artifact card with mana value 2, reveal that card, put it into your hand, then shuffle.

When Trophy Mage enters the battlefield, you may search your library for an artifact card with mana value 3, reveal it, put it into your hand, then shuffle.

Improvise (Your artifacts can help cast this spell. Each artifact you tap after you're done activating mana abilities pays for {1}.) Search your library for an artifact card with mana value X or less, put it onto the battlefield, then shuffle.