Activate Emry by tapping it, targeting Lotus Petal.
Cast Lotus Petal from your graveyard by paying {0}.
Chakram Retriever triggers, untapping Emry.
Activate Lotus Petal by sacrificing it.
Repeat.

Infinite colored mana

Infinite storm count

Emry, Lurker of the Loch

Chakram Retriever

Lotus Petal

Activate Lotus Petal by tapping and sacrificing it, adding one mana of any color.
Activate Emry by tapping it, targeting Lotus Petal.
Cast Lotus Petal from your graveyard by paying {0}.
Chakram Retriever and Sai, Master Thopterist both trigger.
Resolve the Chakram Retriever trigger, untapping Emry.
Resolve the Sai, Master Thopterist trigger, creating a 1/1 Thopter token.
Lotus Petal resolves.
Repeat any number of times.
Activate Sai by paying {1}{U} and sacrificing two Thopter tokens to draw a card.
Repeat the previous step any number of times.

Infinite card draw

Infinite creature tokens

Infinite death triggers

Infinite draw triggers

Infinite ETB

Infinite LTB

Infinite sacrifice triggers

Sai, Master Thopterist

Activate Lotus Petal by tapping and sacrificing it, adding one mana of any color.
Activate Emry by tapping it, targeting Lotus Petal.
Cast Lotus Petal from your graveyard by paying {0}.
Chakram Retriever and Efficient Construction both trigger.
Resolve the Chakram Retriever trigger, untapping Emry.
Resolve the Efficient Construction trigger, creating a 1/1 Thopter token.
Lotus Petal resolves.
Repeat.

Efficient Construction

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