The Mycotyrant

Trample
The Mycotyrant's power and toughness are each equal to the number of creatures you control that are Fungi and/or Saprolings.
At the beginning of your end step, create X 1/1 black Fungus creature tokens with "This creature can't block," where X is the number of times you descended this turn. (You descend each time a permanent card is put into your graveyard from anywhere.)

Undergrowth Scavenger

Undergrowth Scavenger enters with a number of +1/+1 counters on it equal to the number of creature cards in all graveyards.

Utopia Mycon

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.

Mycoloth

Devour 2 (As this enters, you may sacrifice any number of creatures. This creature enters with twice that many +1/+1 counters on it.)
At the beginning of your upkeep, create a 1/1 green Saproling creature token for each +1/+1 counter on Mycoloth.

Savage Thallid

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.

Boneyard Mycodrax

Boneyard Mycodrax's power and toughness are each equal to the number of other creature cards in your graveyard.
Scavenge {4}{B} ({4}{B}, Exile this card from your graveyard: Put a number of +1/+1 counters equal to this card's power on target creature. Scavenge only as a sorcery.)

Thallid Shell-Dweller

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.

Cankerbloom

{1}, Sacrifice Cankerbloom: Choose one —
• Destroy target artifact.
• Destroy target enchantment.
• Proliferate. (Choose any number of permanents and/or players, then give each another counter of each kind already there.)

Sporecrown Thallid

Each other creature you control that's a Fungus or Saproling gets +1/+1.

Tukatongue Thallid

When Tukatongue Thallid dies, create a 1/1 green Saproling creature token.

Deathbloom Thallid

When Deathbloom Thallid dies, create a 1/1 green Saproling creature token.

Yavimaya Sapherd

When Yavimaya Sapherd enters, create a 1/1 green Saproling creature token.

Psychotrope Thallid

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.

Undercellar Myconid

Whenever Undercellar Myconid enters or dies, create a 1/1 green Saproling creature token.
{T}: Add one mana of any color.

Rhizome Lurcher

Undergrowth — Rhizome Lurcher enters with a number of +1/+1 counters on it equal to the number of creature cards in your graveyard.

Sporesower Thallid

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.

Mindbender Spores

Defender (This creature can't attack.)
Flying
Whenever Mindbender Spores blocks a creature, put four fungus counters on that creature. The creature gains "This creature doesn't untap during your untap step if it has a fungus counter on it" and "At the beginning of your upkeep, remove a fungus counter from this creature."

Rot Shambler

Whenever another creature you control dies, put a +1/+1 counter on Rot Shambler.

Molderhulk

Undergrowth — This spell costs {1} less to cast for each creature card in your graveyard.
When Molderhulk enters, return target land card from your graveyard to the battlefield.

Spore Crawler

Blightsower Thallid

When this creature transforms into Blightsower Thallid or dies, create a 1/1 green Phyrexian Saproling creature token.

Blightreaper Thallid

{3}{G/P}: Transform Blightreaper Thallid. Activate only as a sorcery. ({G/P} can be paid with either {G} or 2 life.)

Blightreaper Thallid // Blightsower Thallid

Corpsejack Menace

If one or more +1/+1 counters would be put on a creature you control, twice that many +1/+1 counters are put on it instead.

Thallid Germinator

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.

Swarm Shambler

Swarm Shambler enters with a +1/+1 counter on it.
Whenever a creature you control with a +1/+1 counter on it becomes the target of a spell an opponent controls, create a 1/1 green Insect creature token.
{1}, {T}: Put a +1/+1 counter on Swarm Shambler.

Broodrage Mycoid

At the beginning of your end step, if you descended this turn, create a 1/1 black Fungus creature token with "This creature can't block." (You descended if a permanent card was put into your graveyard from anywhere.)

Myconid Spore Tender

Infesting Spores — When Myconid Spore Tender enters, destroy up to one target artifact or enchantment.

Thallid

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.

Thallid Omnivore

{1}, Sacrifice another creature: Thallid Omnivore gets +2/+2 until end of turn. If a Saproling was sacrificed this way, you gain 2 life.

Akawalli, the Seething Tower

Descend 4 — As long as there are four or more permanent cards in your graveyard, Akawalli, the Seething Tower gets +2/+2 and has trample.
Descend 8 — As long as there are eight or more permanent cards in your graveyard, Akawalli gets an additional +2/+2 and can't be blocked by more than one creature.

Deathspore Thallid

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

Sporemound

Landfall — Whenever a land you control enters, create a 1/1 green Saproling creature token.

Synapse Necromage

When Synapse Necromage dies, create two 1/1 black Fungus creature tokens with "This creature can't block."

Sporoloth Ancient

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."

Slimefoot, the Stowaway

Whenever a Saproling you control dies, Slimefoot, the Stowaway deals 1 damage to each opponent and you gain 1 life.
{4}: Create a 1/1 green Saproling creature token.

Tendril of the Mycotyrant

{5}{G}{G}: Put seven +1/+1 counters on target noncreature land you control. It becomes a 0/0 Fungus creature with haste. It's still a land.