Exchange card sp 5 and 6 for perfection Stones.
1 SP for 1 Perfection
#sp 5 and6 exchange
buoyant epoch
slender epoch
given their slightly-rare drop, 1 trash sp can be equal to 5 or even 10 pps if you ask me
flat stone
If I recall, this has been suggested like 1 million times xD (And rejected because a PP stone rework is ongoing, so any of this may not matter when that's done)