Slimefoot and Squee by paying ({1} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) and sacrificing a Saproling, returning it and up to one other creature card from your graveyard to the battlefield.
When
Slimefoot and Squee and up to one other creature enter the battlefield,
Slimefoot and Squee triggers once, and
Blasting Station triggers for each creature that entered.
Resolve the
Blasting Station abilities, untapping it.
Resolve the
Slimefoot and Squee ability, creating a 1/1 Saproling creature token.
When the Saproling enters the battlefield,
Blasting Station triggers.
Holding priority, if you returned another creature in step 1, activate
Blasting Station by tapping it and sacrificing that creature. If you did not, skip to step 9.
When that creature dies,
Szarel triggers, putting a number of +1/+1 counters equal to
Szarel's power on
Crystalline Crawler.
Resolve the
Blasting Station ability from step 6.
Resolve the
Blasting Station trigger from step 5, untapping it.
Activate
Blasting Station by tapping it and sacrificing
Slimefoot and Squee.
When
Slimefoot and Squee is sacrificed,
Szarel triggers, putting a number of +1/+1 counters equal to
Szarel's power on
Crystalline Crawler.
Resolve the
Blasting Station ability from step 10.
Activate
Crystalline Crawler four times by removing four +1/+1 counters from it, adding ({1} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) .
Repeat.
Notes
This combo can put infinite +1/+1 counters on each creature you control except
Szarel so long as its power is greater than the mana needed to activate the creature's ability from your graveyard.
Results
Infinite LTB.
Infinite ETB.
Infinite colored mana.
Infinite sacrifice triggers.
Infinite death triggers.
Infinite damage.
Infinite +1/+1 counters.
Infinite recursion of creature cards in your graveyard.