I hadn’t seen this article, but this is all making a lot more sense! Thank you!
I have been wanting to do a Legio model, and this article has given me some ideas.
@Brother Lutheriel And if you look at the Insignium Astartes: Legio topic, you'll see four scions of Rogal Dorn (from different Chapters) depicted as members of the Legio (five if you count the helmet of the Executioners veteran, and perhaps more since some Chapters' lineage is unknown and I'm not counting the DIY Chapters' lineage in this).
Hopefully the Index Astartes: Legio Bolter & Chainsword article and the What is the Legio? Explanation and your questions asked and answered topic will answer your question.
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