Alphabet is magic. When you discover alphabet you meet this concept many times: runes used for divination, egyptian priests singing vowels in some shamanic approach (it’s said they used it for healing) and the stories of druids keeping their alphabet in secret, runes from Bornholm are 18 in quantity and it’s said that runes was invented in three groups which makes those 18 into three dice and dice were used for divination (wasn’t sure of that and just googled for dice divination and it seems it was, don’t know how I guessed it but the mere fact christians was prosecuting dice-players made me think that dice represent previous culture somehow. Three roots of the yggdrasil, three norns (fates, moirai, sudices, rodzanice, parcae, and the further I explore this the more confused I am, that’s supposed to pass in time but now it’s all like “in the Lithuanian mythology, Laima (fate, destiny) is often confused with Laimė (good fortune) and Laumė (fairy).[4] Other related deities include Dalia (fate) and Giltinė (The Reaper). Laima was first mentioned in written sources as Laimelea by Wilhelm Martini in the Latin prologue to Lithuanian songs, collected by Daniel Klein and published in 1666.[5] She was also mentioned by Matthäus Prätorius, Jacob Brodowski, Philipp Ruhig and others.[6]1” so I leave it here for now.

Another approach is from Pythagorean tetractys. Which is used for so called plebeyan tree of life, and it’s not completely symmetric because it lacks connections between 1&5, 1&8, 1&9, 2&8, 2&10, 3&7 and 3&9. But if we make it completely symmetric by leaving only neighbouring links we get the tetraktys of 18 letters fit for the Bornholm runes. – the only representation of alphabetic order for runes I found yet, by the way. And it correlates the nordic tree of life having three roots and uroboros eating gnawing those roots to the following image:

1 [5] Narbutas, Ignas. "Senieji lietuvių tikėjimai". Darbai ir dienos (in Lithuanian) (Vytauto Didžiojo Universitetas) 5–7. [6] (Lithuanian) Jonas Zinkus et al., eds. (1985–1988). "Laimės". Tarybų Lietuvos enciklopedija II. Vilnius, Lithuania: Vyriausioji enciklopedijų redakcija. p. 467. LCC 86232954.”)