({4} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) at most available.
Steps
Cast
Nature's Rhythm either from your hand or graveyard by paying at most ({4} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) ({G} magic symbol) , searching your library for
Felidar Guardian and putting it onto the battlefield.
When
Felidar Guardian enters,
Felidar Guardian and
Preston trigger.
Resolve the
Felidar Guardian trigger, blinking another permanent you control.
Resolve the
Preston trigger, creating a token copy of
Felidar Guardian that is a 0/1 Illusion.
When the
Felidar Guardian token enters the battlefield, it triggers, blinking the nontoken
Felidar Guardian.
Repeat from step 2.
Notes
If
Nature's Rhythm is in your hand, ({G} magic symbol) ({G} magic symbol) is removed from the cost. However, if it's in your graveyard, you can tap a creature to also reduce the cost.
Results
Exile all nonland permanents opponents control.
Infinite ETB.
Infinite LTB.
Infinite blinking of permanents.
Infinite creature tokens.
Infinite landfall triggers.
Infinite mana lands you control can produce.
Infinite mana lands you control that enter the battlefield untapped can produce.