Red Ragers: You are a Red Rager. Your Chapter is one of the many mostly unknown founded chapters. No one actually knows what your progenitor legion was.
From Create Your Own Story
You are a Member of the Red Ragers Chapter. A chapter that only very few from outside of your chapter even know to exist. And no one knows your roots. Maybe it is the noble Ultramarines? Or the wild Space Wolves? Maybe you are an experiment to reestablish the gene seed of the nine traitor legions? Or maybe you are one of the two Legions that were whiped out of History? No one alive within the imperium of man and likely beyond can say.
There are only few enemies that could possibly stop you, but unlike most other chapters, you don´t think very good about the agenda to attack aliens just because they dare to exist. So you even have a few alien allies that you meet from time to time.
The Planet with your Fortress-Monastry was destroyed by an unstoppable supernova decades before you were born, but the survivors of your chapter still did not find a new home and is travelling with it´s fleet through the imperium in search for battle, a new home and the answer: their roots.
What is your chapter´s main priority?