Rune Stone
From Jenny Everywhere Wiki
Rune Stones were stones into which Runes were carved.
Rune Stones in the Prime Universe were associated with Norse Mythology and could often be magical. In December 2021, to meet with the goddess Sigyn, Pythagoras-858 and Juliet-178 found a Rune Stone in a clearing in a snowy forest. After Pythe touched the stone with the palm of his hand, it began to glow red before exploding in a flash of white light, releasing large amounts of fog in which the goddess appeared.
Later, in the World Below, the Cupids discovered that Loki was bound on a similar, but much larger, Rune Stone. (PROSE: The Winter Quests)