Activate Fungal Bloom by paying {G}{G}, putting two spore counters on Sporoloth Ancient.
Activate Sporoloth Ancient by removing two spore counters from it, creating two 1/1 Saproling creature tokens.
Activate Utopia Mycon twice by sacrificing the Saprolings, adding {G}{G}.
Repeat.

Infinite death triggers

Infinite creature ETB

Infinite creature LTB

Infinite creature sacrifice triggers

Sporoloth Ancient

Fungal Bloom

Doubling Season

Utopia Mycon

Activate Fungal Bloom by paying {G}{G}, putting two spore counters on Sporoloth Ancient.
Activate Sporoloth Ancient by removing two spore counters from it, creating two 1/1 Saproling creature tokens.
Activate Phyrexian Altar twice by sacrificing the Saprolings, adding {G}{G}.
Repeat.
Activate Fungal Bloom by paying {G}{G}, putting two spore counters on a Fungus you control.
Activate a Fungus by removing two spore counters from it, creating two 1/1 Saproling creature tokens.
Activate Phyrexian Altar twice by sacrificing two Saprolings, adding {G}{G}.
Repeat.

Phyrexian Altar

Activate four Fungi and/or Saprolings by tapping them, adding {G}{G}{G}{G}.
Activate Fungal Bloom by paying {G}{G}{G}{G}, putting two spore counters on a Fungus you control.
Activate a Fungus by removing two spore counters from it, creating a 1/1 Saproling creature token.
When the Saproling enters the battlefield, Intruder Alarm triggers, untapping all creatures.
Repeat.

Infinite creature tokens

Infinite green mana

Infinite untap of creatures

Infinite mana creatures you control can produce

Intruder Alarm

Brightcap Badger // Fungus Frolic

Activate four creatures by tapping them, adding {G}{G}{G}{G}.
Activate Fungal Bloom by paying {G}{G}{G}{G}, putting two spore counters on a Fungus you control.
Activate a Fungus by removing two spore counters from it, creating a 1/1 Saproling creature token.
When the Saproling enters the battlefield, Intruder Alarm triggers, untapping all creatures.
Repeat.

Cryptolith Rite

Combos with "Fungal Bloom"