Runes

Runes are small but powerful catalysts carved from condensed runesponge and infused with knowledge and spells. They're used primarily to teach their consumer the contents of the rune.

Runes are relatively valuable, as runesponge only grows in dark ecosystems around killzones. Once harvested, the separated sponge will survive on its own as long as it has soul, but as with anything dark, so much as being exposed to light begins to rapidly kill it. Once brought back, a large amount of the sponge is filled with soul and then blasted with light, where it shrivels and hardens into a stone-like substance that can be infused with any type of thought like a spell, memory or knowledge. A rune the size of a golf ball can hold the knowledge of an elaborate spell, but is condensed from a piece of sponge the size of an entire mattress. The danger of retrieving the sponge is so great that getting the sponge to make one rune either requires multiple trips or an entire party, which is ideal given the danger of the permadark.