A light purple stone, Crystal Marrow grows on the bones of the serpent God, Orobashi. Until the addition of Sayu, they could only be used to complete quests like Gazing Three Thousand Miles Away. Now, they are used as ascension material to level characters.
The following characters require Crystal Marrow for ascension:
A crystal that contains a sliver of Tatarigami power. Adding this material during smelting will greatly increase the strength and toughness of metals. In Inazuma, “Tatarigami” refers to the corpse of a divine being and the strange phenomena it creates. They say that before the god that created Crystal Marrow became the Tatarigami, it had many names, one of which was “Orobashi no Mikoto.” Orobashi no Mikoto’s body was as long as the winding seashore, and its voice was so resounding that only the Dark Sea could absorb it. Yet in the end, it too was cut down together with Yashiori Island itself.
Since Crystal Marrow grows on the remains of the serpent god, Orobashi no Mikoto, it can only be found on Yashiori Island and Tatarasuna.
The majority of Crystal Marrow chunks can be found on Yashiori Island. Simply follow along the skeletal remains of the massive serpent across the map!
To start farming, teleport to the Waypoint near Fort Mumei. From there, start examining the bones of Orobashi. Crystal Marrow usually grows on the ground near them. But sometimes, it can be found on the bones themselves.
After collecting all the marrow, walk in the direction of Fort Fujitou. Over there, you’ll find the Sangonomiya Resistance Camp. Outside the camp are a few bones that have marrow growing on them. Pick those up and keep walking. Do not teleport. While the world map does show certain remains, it doesn’t show them all. If you teleport from one location to another, you’ll miss out on marrow chunks.
Serpent’s Spine (not to be confused with the weapon)
Glide across Musoujin Gorge and you’ll reach the Orobashi’s spine. Over here, Crystal Marrow can be found on the ground as well as bones themselves.
Collect them all and walk towards the Serpent’s Head. The majority of Crystal Marrow grows in this part of the island. For this one specifically, you’ll have to scale Orobashi’s bones from top to bottom.
Jakotsu Mine itself only has one piece of Crystal Marrow chunk to offer. It grows on one of the bones right at the entrance. The rest of the marrows can be found on the bones outside the mine. In this area, there is a Cryo Cicin Mage roaming about so be careful while farming.
Another thing to note is that Crystal Marrow grows on top of the bones as well. Remember to climb them all the way up so you don’t miss out.
Finally, there are a few bones in the water near the mine as well. Make sure to either glide across or swim to them and collect those pieces.
Tatarasuna only has a few Crystal Marrow chunks to offer. To collect them, make sure to finish at least the first part of the world quest Tatara Tales. There is a barrier that surrounds this area so as to bring it down, this quest needs to be done.
Once you’ve unlocked the Mikage Furnace, teleport to the waypoint closest to it. From there, if you follow the small ravine that leads into the furnace, you’ll find all the Crystal Marrow pieces. Just make sure to use an Electrogranum. If you go into deep without it, you’ll slowly start losing HP.
Crystal Marrow respawns within the span of two-three days. After that, you can visit the places noted above and have enough to ascend your favourite characters.