Then he'll do that. He keeps part of his attention on listening for noises in his surroundings, but mostly focuses inward.
...First, he pieces together all the critical memories of who Tarek was, because for some reason this feels very important - get him back someday - he isn't sure why he believes this is even possible, yet, but he drags together some basic mnemonic techniques, half-reinventing them on the spot, and memorizes the key facts about Tarek that would let him pick the youngster out from a lineup of all the humans who ever lived in Velgarth–
–there are worlds other than Velgarth, because he remembers being in one. Tarek spoke Rethwellani and trade-tongue; Leareth can piggyback on that. The language he remembers at all from his previous life is - probably from the other world? It's very pretty.
He remembers a Herald of Valdemar whose name is Vanyel, standing in a frozen pass - a dream - and talking to him. Also the torture memory has Vanyel in it, which doesn't make sense. It wasn't really Vanyel, though? He's pretty confident of that, it was a trick somehow, but he'll have to wait until he's fit together more of the loose puzzle-pieces to see the full picture.
He remembers a man who doesn't quite look human - what was his name - at least ten of the most central memories of his last life are of him, actually. The one with the stars, seen through eyes that weren't his. Having his hair elaborately braided, which for some reason feels very significant and meaningful. The man standing in the ruins of a fortress, briefly making eye contact before gesturing for someone else to club Leareth in the head.
He remembers facing a - god? No, there are two memories there, actually. A man ten feet tall, standing by a forge, handling the red-hot metal barehanded. YOU WANT TO BUILD SOMETHING. I CAN TELL WHEN PEOPLE WANT TO BUILD SOMETHING. PEOPLE WHO WANT TO BUILD SOMETHING AS INTENSELY AS YOU ARE RARE. I WISH YOU GOOD SKILL.
And a different time. Eru likes beautiful stories, and Eru thinks that the most beautiful stories are the stories of how people are utterly destroyed by what should have been their greatest strengths. I am not the enemy of the peoples of Arda except incidentally. I am the enemy of their god.
Leareth knows that in the second memory, he was about to make a terrible mistake. It's frustrating that he isn't sure what the mistake was. They were - at war? With an evil god. Probably this is related to the part where he was being tortured at some point.
He remembers watching the first sunset in a new world that never had a sun until now, with the man whose name he still can't remember. The man was so happy.
He remembers the man holding him, singing a mourning song for - what? It was for him, he thinks, but that's very confusing. Leareth is pretty sure that waking up in a new body is not always this confusing.
–And he remembers telling the man to put him down. I will not forget you and I will come looking. I promise. And the man answering, Love you, and - walking out toward an army, gryphons bearing Vkandis' standard, and going out in a blaze of fire, and how in that moment he wasn't afraid.
He is so incredibly confused, still, but he can already tell, as he pieces the fragments of himself together, that the current situation is very bad.