Creating a Horus Heresy Astartes character

As Cubicle 7 is working on a Horus Heresy RPG and I've been on a bit of a Horus Heresy kick myself recently, I've come with with a series of questions that will help anyone create a well fleshed-out Astartes character.    If you'd rather answer these questions in a Google Form format, you can do so here:  https://docs.google.com/forms/d/e/1FAIpQLSdUHEUV6TxMeoXdWJNa7i8xqfKrB6TyMWH9aMaC1P2d5of9Kw/viewform   1) Which Legion do you belong to?
  2) What planet were you born on?
  3) Who were your parents?
  4) What was your training like? Did you come close to failing/dying — either due to a trial or for genetic reasons? How old were you when the process started?
  5) Have you served alongside another Legion? If so, what tactics and comrades did you learn/gain? Was it a positive or negative experience? Did it challenge your perspective on your legion/Primarch?   6) Are you a 'typical' member of your legion, mindset-wise? Or do some whisper that you would have been a better fit for another legion? If yes, did you begin as an aspirant for another Legion and then got reassigned part-way through your training?   7) Were you an Astartes before your Primarch was rediscovered? Did you ever fight in your Legion's old colours?

8) What is your current rank? How did you earn it? Does it fit you? Are you ambitious? Have you ever been demoted and if so, why?   9) What are your strengths?   10) What are your weaknesses?   11) What are your thoughts on The Imperial Truth? You may wish to consider your experience with Warp Travel when answering this question.   12) How concerned were you that the Great Crusade was nearing an end?   13) How did you feel about Horus being made Warmaster (and not your Primarch — if you're not of the XVIth)?   14) How did you feel about the Emperor abandoning the Great Crusade?   15) Did you attend the Triumph of Ullanor? If so, how did it affect you?   16) What is your attitude to Remembrancers?    17) Are you aware of the Lectitio Divinitatus? If so, what do you think about it?   18) What foes did you mostly face during the Great Crusade?   19) How did your first combat against other Astartes play out?   20) How are you coping/adapting with/to the trauma and horrendous attrition rate caused by Astartes vs Astartes conflict (e.g. rapid loss of comrades, lots of replacement bionics, having to lead/fight alongside raw recruits) — Note: this is more for mid-to-late in the Horus Heresy then the opening massacres.   21) What do you think of your Primarch (particularly in terms of their 'infallibility')?   22) Have you ever met the Emperor? If so, what happened and how did it affect you?   23) What do you think is the likely outcome of the Horus Heresy? What scares or excites you the most?   24) How much devastation have you witnessed due to the Horus Heresy so far? How has it affected you?   25) What is your view of mortal humanity? Are you close to any baseline humans or do you keep yourself apart from them?   26) Have you been forced to kill your Legion brothers?   27) [Loyalist only] If your Primarch is missing/dead — how has this affected you?   28) [Loyalist only] How did you learn of Horus's betrayal (and/or that of your Primarch)?   29) [Loyalist only] How close were you to turning traitor?   30) [Traitor only] What convinced you to side with Horus (and or your traitor Primarch)? Did you do so at the same time as the rest of your Legion/force or were you an early or late convert?   31) [Traitor only] Do you harbour doubts about the rightness of your cause?   32) [Traitor only] How much do you know about the Chaos Gods and how willing are you to embrace their gifts?   33) [Traitor only] Do you genuinely think that the Imperium will be better under Horus?