All events have a similar shop, and you should ALWAYS aim to clear them out when hardmode opens. After hardmode opens, don’t forget to buy the extra tries on the top left and farm core dust on the event itself, usually stage 11.
If you buy all the extra tries, this allows you to clear the whole shop as long as you are using the NIKKE that give increased chance for event materials to drop and get 1-3 extra synchro levels per event.
You get currency here by doing Union Raids. You can also obtain batteries for your cubes doing Solo Raid when it’s available. A lot of people ignore cubes and just buy dupes of their waifus in this shop, honestly your pick since cubes will naturally level up over time thanks to the Raids.
You get currency every day on your mail depending on your Arena rank and also every time you do PVP. This is probably the worst shop in the game right now in terms of what you can buy.
Same as the body labels, you obtain tickets every time you pull. Silver tickets for normal banner and gold tickets for limited character pick up banners.
You can only obtain this currency when the coop events are available, make sure you do them always since it’s free extra resources.
I buy everything resource related and ignore the gifts since long term you get more than enough.