The battle is over , conquistada has been lost, most of the remaining solders got killed in sight if they where wounded heavily, spared if not. Dax thornhil hid in a nearby cave, hoping the hostile solders wouldnt find him and he could escape, but, someone was inside the cave already.
A really tall silver, dragonborn looking fella walked towards him, he grabbed dax by the shoulder and told him to run inside, so they did. The cave was lit by green bright crystals, it looked as the dragonborn was living here permanently, without any stress of the outside world. So he asked for a favor, since he helped him escape from being captive,"i need you to find my brother, he is a jade dragonborn living in another plane of existence, far from here", hesitant, Dax refused , " i cannot leave my family behind, not again, I've lost enough already" he said with a trembling voice.I will give you enough power to make mere mortals tremble from your existence, ill make you an unstoppable force, tou you are already strong enough by yourself, i saw you in the battle, but with a little help my me, you will spread fear and dread every time someone dares to challenge you.
Dax thought about his choices for a while, he could try to escape the cave, but he has no idea of what the other dragonborn is capable of, or just go with his plans and help him for as long as he needs, he chose the latter.
Alight, since you agreed , you might as well see my actual form, the one you will have as well, it will sting a bit and you will fall unconscious but fear not!
As he said that, his form started changing, bones came off his back forming a pair of skeletal wings, his ribcage opened and formed a short of armor , protecting his chest piece, his legs and arms started growing as well, and when his transformation was over, he pulled a large greatsword from his back, and stabbed with it Dax in the stomach.
"this is my gift to you" he whispered, as dax coughed blood and slowly faded away.
Dax woke up in a world unknown to him, it was quite cold, it felt as he was back in Firras but it didn't feel right, his stomach wound was nowhere to be found, and he still had the greatsword with him, he could feel the new surge of power flowing within him,but couldn't quite use it yet, now, he is searching around the cities for clues on where to start.

For context, Dax is the father of my other character, Dokris thornhil, he is in a separate campain that takes place in a separate universe sadly.