Traditionally Loki is also a shape shifter in classical lore. In some of the old texts Loki is actually the father of the world serpent which raises questions here but would explain why the Serpent says Atreus looks familiar when they first meet. A lot of the legends Mimir talks of in the boat would have technically had Loki involved classically so we're already straying from the source material. God of War has always played loose with its source material so the fact that Atreus' 'real' name from his mother is Loki doesn't really give us much to go on.

Atreus is Loki, but how does that fit in to Norse mythology? The game is meant to use Elder Futhark runes, but following that for translations gives you '?ndlal foluo hormung' - the first letter doesn't seem to have a direct Futhark representation, although 'hormung' is close to an old word for 'descendants'. I've tried translating the runes around that image as well but it's either gibberish or an anagram. In the original games Kratos killed his own family in Greece as a result of Zeus manipulating his rage. We even see Atreus shoot his Kratos after he destroys the first gateway to Jotunheim so we know he's capable of rage-based impulsiveness. Is he helping him? Healing him? Talking? The game puts a lot of effort into making you think about patricide, so it's looking a little bleak. We also see this image above in Jotunheim, showing Atreus bending over Kratos, apparently linked in someway by a rope like line. Kratos later admits he killed his own father, Zeus, which becomes a more significant admission as a result. There's a side mission involving a bandit stabbed in the back by his own child, which Atreus fixates on a lot (he can't understand how anyone could do that).

Fathers killing sons is a reoccurring theme in God of War.

God of war symbol