1 Answers
You purchase them, or you earn them by completing the levels in the Constellation.
You can earn 50 free gems on tier 18 on each of the 3 levels in the Constellation. You complete the tiers by earning Pogis, and you do that by completing Daily Challenges, Weekly Challenges, Marathon/Event Badges, and M&M Badges.
But the only way to get them when you want them is to buy them.
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