for no reason this normal theme is so easy to get (for me) i even got 4 prisms already 😫 (no flex, fr) anyway that 10 prism pack in waterbomb event might help you get a prism 👀 (orrrrr... you've already claimed it, awkwarddd...) but either way good luck 🍀
i'm currently using SEEUN's Artist Pack. she's my bias in STAYC 😂 i recommend saving 💎 up to buy Live Theme first. Artist Packs are always available for you to purchase, but the Live Theme is only up for a certain period of time.
i tried not to buy any Limited Theme for half a year 😵 i also tried my best to complete weekly missions + monthly progession, watch ads and upgrade my cards to get more rewards on the World Record. i hope that you can collect 💎 as much as you want in the future!