You have at least one +1/+1 counter on a creature you control.
Mana Needed
({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) .