Tips for creating a fully fleshed-out Space Marine character set in the Horus Heresy

As an avid reader/listener of Horus Heresy novels, the Black Books and a big RPG geek, I’m really looking forward to the upcoming Horus Heresy RPG by Cubicle 7. With this in mind, I’ve put together the following list of questions to help you create the background for your Horus Heresy Space Marine character.

Whether you want to get prepared before the RPG is released, just want to create some background for your miniatures or are writing some Horus Heresy fiction of your own, this article is for you.

After you’ve picked a Legion (even if you’re creating a Blackshield, I’d recommend doing so) and whether you are a loyalist or a traitor, take a stab at answering the questions below. While answering them, remember that competence and combat prowess are a given for Astartes and therefore are not interesting character traits. For the sake of brevity “You” refers to the character you’re creating.

This article isn’t going to delve heavily into personality traits (like empathy or how authoritarian your character is), but these should inform your answers. One key thing to bear in mind is that Hypno-Indoctrination in this era was significantly milder than that from the Scouring onwards. Therefore, Astartes’ emotions and thought-processes are far more human-like than they are in the Warhammer 40,000 setting. Going by the Horus Heresy novels, the only real differences are no sex drive, ’no fear’, often vastly improved memories/focus/clarity/speed of thought and reaction speeds, along with the tendency to mirror your Primarch’s preferences.

General questions

What planet were you born on and what was it like to grow up there?
The three main options are:
A) Terra
B) Your Primarch’s home world
C) Another planet that serves as a secondary recruiting ground for your Legion.
If you `are creating a Traitor, then B) is the default, as many of the Terran-born marines within the Traitor Legions sided with the loyalists (before being mostly culled at Isstvan III).

Who were your parents? What social strata did you occupy?

What characteristics singled you for recruitment by a Legion?

Were you recruited despite some of your physical traits?

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?
One possible option here is that you were one of the few adult humans who fought for your Primarch on his home world before he was reunited with the Emperor and survived ascension. This is particularly fitting for high-ranking officers who are very close to and loyal to their Primarch and his ideals.

What were your relationships like with the aspirants you trained with? Do any of them serve alongside you? Are you responsible for any of them being injured or killed during training and if so, how has that affected you?

Has something gone wrong (either physically or mentally) during your creation?
For example, are you ‘too human’ in some way, like being traumatised by being taken from your parents? This could be an interesting way to inject some ‘imposter syndrome’ – you might be an over-achiever compensating for a flaw that you refuse to admit to.

How much do you remember of your pre-ascension life?
This is quite tied to how human you are emotionally and how well you get on with non-ascended humans. If you’re a pretty inhuman Iron Hand for example, it’s fitting for you to not remember much of your life as a child. However, having flashbacks to it after performing a particularly callous act could be a great way to build character.

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 change your perspective on your legion and/or Primarch?

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? How does that affect you when you come into contact with that Legion?
Your answers to this and the question above, are a great way of injecting more variety into a campaign where all the characters are from the same Legion. I’d advise against being simply being a stereotypical example of one Legion but serving in another. For example, consider how one Legion might put its own spin on another Legion’s favourite tactic.

How much do you agree with the statement ‘The end justifies the means’?

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?

If you are an officer of high rank, how do you feel about the distance it creates between you and the front line? Do you rail against it? What has it done to your combat prowess (or your perception of it)?

What are your strengths and greatest achievements/victories?
What are your weaknesses and greatest failures/defeats?
With this and the previous question, have your victories and defeats arise from your personality traits and your approach to war. For example, if you’re very analytical, then your greatest victory might be against a rational foe, but your greatest defeat might have been against the Orks or a similarly irrational foe like the Thyrrus. It’s also worth thinking about how you reacted to your victories and defeats. Do you brood on the latter and/or feel guilt? To what extent have you learned from them or are you likely to keep making the same mistakes?

Have you ever been severely injured (e.g. enough to trigger your Sus-an Membrane)? If so, what caused it? How did the resulting period of convalescence affect you?

What are your thoughts on The Imperial Truth? Consider your experience with Warp Travel when answering this question.
Note that some Legions bought into the Imperial Truth far less than others – the obvious ones being the White Scars, Thousand Sons and Word Bearers.

Were you a lodge member before the Heresy? If not, were you asked to join and if so, why did you refuse?

What do you think of your Primarch? How much do you idolise him?

How close are you to your Primarch and his inner circle? Are you part of it or are you barely known to them?

Rank the following in descending order of your loyalty (delete whichever aren’t applicable given your choice of loyalist or traitor): Humanity, The Imperium, The Emperor, The Warmaster, your Primarch, your Legion, your battle-brothers.

What is your preferred approach to personal combat? Does it differ from your Legion’s norm?

Are you a psyker gifted? If yes, how did your powers first manifest? What you do think about them? Are you suppressing your powers in accordance with the Edict of Nikaea? If so, how does this make you feel?

If you’re a Blackshield, what caused you to strike your Legion’s colours from your armour? What motivates you to fight and what are your goals?


The Great Crusade
Were you an Astartes before your Primarch was rediscovered? Did you ever fight in your Legion's old colours? If you remember the Legion before its Primarch was found, how do you feel about the changes they have made?

What foes did you mostly face during the Great Crusade? What foe did you most prefer fighting? Which did you dislike fighting the most?

Which Imperial forces did you fight alongside the most and how has this shaped your views of them?


Events immediately prior to the Heresy
How did you feel about Horus being made Warmaster (and not your Primarch)?

Did you attend the Triumph of Ullanor and if so, how did it make you feel? 

Were you involved in the Council of Nikaea? If so, were you for or against the Librarius?

What do you think about the Burning of Prospero? Did it change the way you view the Emperor and/or the Space Wolves?


Your thoughts on the Emperor
How did you feel about the Emperor abandoning the Great Crusade?

Have you ever met the Emperor? If so, what happened and how did it affect you?

Are you aware of the Lectitio Divinitatus? If so, what do you think about it?


How you relate to normal humans
What is your view of mortal humanity?

Are you close to any baseline humans or do you keep yourself apart from them?

To what extent can you emphasise with and understand human weaknesses? How does having to account for them make you feel?

What is your attitude to Remembrancers? 

Mid-Heresy - general questions
How did your first combat encounter against other Astartes play out?

Are you on the side you are due to a decision you’ve made or is it just happenstance?
The latter is likely to be the case for the rank-and-file, but isn’t very satisfying when creating an officer.

How are you coping with or adapting 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 or fight alongside raw recruits)?
Note: this is more for mid-to-late in the Horus Heresy then the opening massacres.

What do you think is the likely outcome of the Horus Heresy? What scares or excites you the most?

How much devastation have you witnessed due to the Horus Heresy so far? How has it affected you?

Have you been forced to kill your Legion brothers? If so, how has it affected you?


Mid-Heresy - Loyalist only
If your Primarch is missing/dead — how has this affected you?

How did you learn of Horus's betrayal (and/or that of your Primarch)?

How close were you to turning traitor?

Which traitor Legion(s) do you hate most and why?

How much has the Heresy affected your ability to fully trust anyone?


Mid-Heresy - 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?

Do you harbour doubts about the rightness of your cause or do you genuinely think that the Imperium will be better under Horus?

How much do you know about the Chaos Gods and how willing are you to embrace their gifts?

Thanks for reading! Please let me know if there’s anything I’ve missed and please share your creations, I’d love to see what you come up with.