You have at least one +1/+1 counter on a creature you control.
({1} magic symbol) ({G} magic symbol) available.
Steps
Activate Ooze Flux by paying ({1} magic symbol) ({G} magic symbol) and removing a +1/+1 counter from a creature you control, creating two 1/1 Ooze creature tokens.
Rosie Cotton of South Lane triggers twice, putting two +1/+1 counters on Crystalline Crawler and any other creature you control due to Primal Vigor.
When the Oozes enters the battlefield, Sigil Captain triggers twice, putting four +1/+1 counters on each of them due to Primal Vigor.
Activate Crystalline Crawler's first ability twice by removing two +1/+1 counters from it, adding ({1} magic symbol) ({G} magic symbol) .