Activate Argothian Elder by tapping it, untapping Griffin Canyon and another land.
Activate Griffin Canyon's second ability by tapping it, untapping Argothian Elder and giving it +1/+1 until end of turn.
Repeat.

Infinite mana lands you control can produce

Infinitely large creature until end of turn

Infinite untap of lands you control

Argothian Elder

Griffin Canyon

Maskwood Nexus

Leyline of Transformation

Arcane Adaptation

Activate Oko's first loyalty ability by putting two loyalty counters on it, causing Argothian Elder to gain all creature types.
Activate Argothian Elder by tapping it, untapping Griffin Canyon and another land.
Activate Griffin Canyon's second ability by tapping it, untapping Argothian Elder and giving it +1/+1 until end of turn.
Repeat from step 2.

Oko, Lorwyn Liege // Oko, Shadowmoor Scion

Activate Griffin Canyon's first ability by tapping it, adding {C}.
Activate Unnatural Selection by paying {1}, causing Argothian Elder to become a Griffin until end of turn.
Activate Argothian Elder by tapping it, untapping Griffin Canyon and another land.
Activate Griffin Canyon's second ability by tapping it, untapping Argothian Elder and giving it +1/+1 until end of turn.
Repeat from step 3.

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