He always has trouble with his first memories.
They're scattered, after all, and he doesn't exist yet, in them.
The clearest ones are from the live whelp. He vaguely remembers his mother. He remembers caring deeply for her, and hurting, when he was taken away and his neck was snapped. He remembers dying. That isn't something you forget.
The eggs are... vaguer. He remembers being cold and alone twice over, and far, far from home. He remembers reaching out and finding nothing. He remembers voices speaking in languages he hasn't been taught yet.
Then he remembers that. The searing pain - not once, but three times, cauterising its way agonisingly through every nerve in his limbs where it cuts, torching out the corruption and leaving pure hurt instead.
And not just his body, either - forcing years upon thousands of years of not knowledge, not information, but pure data into a mind barely prepared to learn the Common tongue? Hardly something pleasant.
But it's what made him. And without it, he would not exist. Did not exist. He has a millennium or two, sometimes, he thinks, of data in his mind which feels like it belongs to him - yet he has to remind himself, he did not live these things. They are not, technically, his.
Wrathion doesn't think about the past much. He doesn't really have a reason to unless there's something he can gain from it; Titan artefacts and world history are all very much of interest to him if they can help him prepare against the Legion, but...
It's impersonal. It might be in his mind, but it's not his. When he makes it anything else, he has memories like that which make him shake and fight not to empty his stomach. He didn't even have the titan-granted knowledge to understand what was happening, when those things occured to him. Them. Him. Them. He's never sure, if it counts or not.
And thinking about it serves no purpose, so he buries it under the Blue Child's visions of a shattered Azeroth and the bright, dazzling memories of Anduin Wrynn. At least those things can allow him - and Azeroth - to continue moving forwards.