Rare prism shop

I'd say to just get the lore from the events. Imo it's not worth burning 5 sr or 1 ssr servant for crystalized lore

Burn all your servants and buy lores, it's worth it.

Do you have a surplus of servants and have skills stuck at lvl 9, maybe it's worth it. If you don't have the servants to spare and still have a back log of event lores because you are in qp hell...definitely not worth it.