I got to be honest with you, i don't remember shit from the early chapters, it's been 4 years. And the only spirits i have seen are the small ones that seem to just go of emotional and simple verbal clues. i didn't even remember there were any higher tier of spirit as it never came up again.
I just looked at chapter 1. "They don't grow old. High Elves live for more than a thousand years, and once their physical form perishes, their spirit goes on to linger in nature until the end of the world itself." And the illustrations is just the small spirits we always see.
Yea same, 2-3y for me, I only vaguely remembered about it too, I rechecked briefly early chapters to refresh on the few glimpses we had on high elf life for this arc, was surprised to find the higher spirit chapter so early yet nothing rly was said and nothing after (unless some higher creature that was shown are counted as higher spirit but wasn't directly said). And no clarification of what type of spirit they become (indeed that image, but higher spirit existance is only revealed later, tho very soon) nor what is "higher" vs normal spirit even is (born that way? can one evolve or devolve into it?), was all left vague (tbf as many things in this manga are, esp on its "magic beings system").
At best we could assume there is at least a difference for elders as high elf guy asked him this ch "did they not come to you?", with MC not saying anything along the lines of "even if they did, it would be hard to tell them apart".
I somehow remember even less details with the chinese continent arc, if those "higher beings" (guardians?) around the dragon counted in some way as "spirit / higher spiritual individuals" (but since he was still the strongest/most important there for being a "higher elf", would still leave it as only him being the potential higher spirit) .. also the whole thing with japan arc and some giant that sat in that tree (tho I think that was some deity or demi-god).
Well we might finally get answers this arc, sad part is that with the release speed this series has, it might take another 1-2y to get them.