"If we'd interfered directly back then, that old man Odin would never have failed to notice," another shadow murmured. Its voice was rough and muffled, like gravel grinding across an anvil.
"Don't forget: when the Celestials attacked, we secretly influenced the prophecy of fate.
"We guided him to sacrifice himself on the World Tree and hang upside down until the ninth day. Only then did we transfer a portion of the World Tree's power to him. Even so, he still vaguely sensed our presence."
A third shadow joined the conversation. Its voice was a little sharper than the first two, like a drawn-out metal wire vibrating:
"We can hardly blame ourselves. We never appeared before him. We merely inscribed the World Tree's power as ancient runes in the blood he shed and let him decipher them himself.
"Who knew he could detect something wrong even then? Afterward, Odin not only became aware of us but secretly began plotting to prevent Ragnarok.
"That shows Odin is far more cunning than his father, Bor. We didn't anticipate that."
A brief silence passed among the shadows. Then a fourth voice spoke, deeper than the others and heavy with something close to a sigh:
"There's no use talking about that now. But Odin gaining that power wasn't entirely bad for us. He stopped the Celestials' attack and protected the peace of the Nine Realms.
"Without him, invasions from beyond this universe would have caused far worse damage to the World Tree."
The vast beings hidden deep in the World Tree's shadow exchanged information in their own peculiar way. Their tones were casual and unhurried, as though the survival of the entire Nine Realms were merely one move on their board.
They were called the Shadow Elder Gods. Their history stretched back to the formation