@Concise619 what @HanSoloWannaBe is referring to are the unlock symbols on my screen shot below:
These icons on the battle event mean you will unlock the ability to purchase that creature for DNA in the market. Generally the even to unlock a creature comes around once a year, every week is an opportunity to unlock at least one creature. The battle event, I think it is called the arena is another way to unlock creatures for purchase.
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