system
Given the following post, respond as if you're commenting on Reddit:
human
[Avatar, post LoK] could Proto-Avatars now exist by making pacts with Spirits?

Basically, The Avatar can hold All Four Elements inside themself because Raava is Basically acting as extra storage for their Sparks.

But there are a lot of great and powerful Spirits in The Spirit World, so could someone step through one of the portals and potentially make a Pact with one to hold an extra Element or 3?
gpt
Conceivably, yes, but its slightly more then "get a powerful spirit".

You need a powerful spirit who is given the ability to bend all four elements by the lion turtles- note the "dark avatar" can still just waterbend. Your spirit ally means you can be granted more then one element, but you still need to be granted them.

This is still theoretically possible- there are still a handful of lion turtles around- but its gonna be a lot harder then in prehistory.