#yall looking at how much souls games influenced my perception like spongebob in-

[katyspersonal]

SOULs ideas (Undertale)

I think it still works the best that originally monsters appeared from souls of dead humans that were unable to find rest! Human souls in lore have some magic to them too and they are colored as either rainbow color, whereas monster souls are white (so all rainbow colors in one) and are human souls upside down... like, yeah.

So what if the restless souls struggle and linger until the point where remaining determination in them expires to give them second shot at life, so they change into new form - forgetting all about their previous life? Monsters' bodies are magical and can even evolve into shapes of objects, not only animals, however monsters that appear like this might have traces of their former personality reflected in new shape. And, well... pure magic can just create more of itself, so they can reproduce on their own too.

Bravery SOULs would not be able to find rest if their death had no honor to it (like maybe some really embarrassing lethal accident)! Justice SOULs, naturally, would not be able to rest if their death wasn't fair or they crave comeuppance/revenge for other reasons. Integrity SOULs would be held back by unfinished business, like promise they didn't get to keep, and Patience SOULs are probably the most frequent to accept death, only lingering if they have means to wait for being found but no longer.

Kindness and Perseverance SOULs are, on the contrary, probably the most frequent ones to linger long enough. Kindness would be too concerned for friends and family they left like that, and Perseverance would just try to adapt to this new "lifestyle" - most commonly acting like a poltergeist for a while, and almost exclusively becoming Ghost monsters.

Red SOULs are both the most powerful and the most helpless ones, since they are in tune with Angel! They are especially perceptive and intuitive to the divine, able to extend powers of other SOUL types when needed, never sure whether by their own volition or because of the power that guides them (not just the player, superior forces within lore in general!). Typically they cannot rest if their divine guidance abandoned them but they lack Determination to dial time back on their own. They are the ones to turn into boss monsters!

It just seems like visual symbolism of the whole thing is very appropriate, imo! As well as people going at each other's throats forgetting that half of them used to be the other half once... because we live in a society, indeed. And after Monsters got sealed underground, humans take care of restless SOULs on their own to not allow any monsters. Maybe they have specific priests for that! And maybe some SOULs still remain undetected and become monsters, so humans hunt those down in secret societies, trying to keep the fact that humans can get second shot at life if they know what to do from the crowd? Haha, many ideas