abyssal pearl and moonstone
The story of nami has been enriched as the lore evolves: first with the new lore of the vastayas, then with her comic. but we still don t really know what the abyssl pearl is.
first, I'll make some assumptions, then I'll explain my theories. Nami is a vastaya, so she lives with her tribe near a magical place. we can therefore assume that the magic sticks of the marais have a relationship with spiritual magic. Moreover, it is almost certain that the monsters that threaten the marais are voidborn (we can suppose that the void breach was opened by the watchers because of the magical nature of the place)
therefore, we know that the marais must fetch the abyssal pearl which lies near the void breach. Here is my theory: in contact to the void, spiritual magic is brought together, which forms this brilliant "pearl". this strong magical concentration prevents the void from consuming it (indeed the void feeds on organic and magical matter) this explains that the voidborn of the comic doesn t consume the pearl, and that it is located near the breach of the void.
The tidecaller will therefore look for this pearl, and must make the exchange with the aspect of the moon, which creates a moonstone. this moonstone is of celestial origin and creates a lot of light. But why does the aspect need the pearl ? we know that diana fights the void: so this pearl ,which prevents the corruption of the void, is very useful to her. I noticed that kassadin uses a similar stone in his color story: "In my other hand, I clutch the stone tightly. Its foreign magic has kept me alive this long—long enough to delve far, far beneath the wastelands of old Icathia. It holds your corruption at bay, though at what cost to my flesh and my spirit, I cannot guess, for this smallest of trinkets now thrums in time with my own heart. That fearful rhythm is not the pulse of life, or magic, or any other wholesome thing, but of oblivion itself. Of that much, I am certain." so this exchange allows the aspect to fight the void without fear of corruption, and the light of the moonstone makes possible to scare voidborns in order to protect an entire tribe. I think this idea is great, because it allows to connect different things in the lore of nami: the void, the magic of the vastayas and the aspect of the moon. But these are just theories. Thank you for reading and sorry for my bad english. [slayer-jinx-catface]