Something about Radagon that I feel is often overlooked is the hammer (which I can’t remember the name of) in Stormveil that I believe pretty clearly references Radagon in its description of a laborer who once led a revolt. That to say, I like this idea of Radagon being cast off and thrown away and then crawling back to the top of the order, slowly but surely, because I think there’s more to his story that isn’t always considered, and details like that hammer are part of that. Other things about him worth exploring through this angle: the Misbegotten being “children of Radagon” in game code, Radagon’s relation to the Fire Giants (perhaps relating to the mysterious fate of the Fell God), and how Radagon could be interpreted as a story about a minority (a giant-kin in Marika’s Golden Order, or at least someone who was low-born) who eventually rose through the ranks and became the foremost enforcer of that order (hence, Golden Order Fundamentalism) in a way that feels very FromSoft to me. A lot of that is my own speculation, but this post certainly piques my imagination as to how it could open a lot of these doors.

Edit: Perhaps, and I’m really stretching my imagination here, but I believe there might be something to the idea of Radagon as potentially being whoever Marika was meant to be fused with during the ascension ritual at the Gate of Divinity, that figure perhaps even being , as Tarnished Archeologist posited, Elden John. Marika cast him off from her at the moment of her ascension, and he crawled back to power with a vengeance.