I was very jarred by chapter 448 and beyond until the reveal and kind of want to quit reading but this isn't fully about that. Even after the reveal, like when the heck did Ouranos give the mc the scroll. Did future Ouranos use the scroll and suck in past mc or something? I don't remember any mention of a gift from Ouranos before chapter 448 so I am kind of confused a fair bit. Honestly, I ain't even read after 448 and just skimmed because I wasn't in the mood for a tone shift. Just as a side tangent whenever a past version of the mc sees into the future it just skips character development to me at least and even in cases where it's not the past self inheriting everything it still doesn't work well. They change way too much too quickly.
I can't remember well since it's been a lot of time since i read it, but i remember Eina giving him that gift (i read it around a year ago)