Rhiannon Matthias

Rhiannon's best friend is Violet Sorrengail, and their relationship is the emotional backbone of her arc in Iron Flame. She fiercely supports Violet throughout their second year at Basgiath War College, though her loyalty is grounded in honesty rather than blind devotion—a distinction that becomes critical when she discovers how much Violet has been hiding from her.

Rhiannon confronts Violet because Violet concealed the existence of the venin and the true purpose of the wards—information that directly affects whether every rider at Basgiath lives or dies. For Rhiannon, this is not a forgivable lapse in judgment but a fundamental breach of trust: she argues that genuine friendship cannot coexist with deception that strips someone of agency over their own survival.

Rhiannon ultimately chooses solidarity over her justifiable grievance, returning to Violet's inner circle and fighting alongside her at Aretia and beyond. Her return is not a quiet retreat, however—she comes back on her own terms, having decided that confronting the venin threat outweighs harboring resentment. The reconciliation is hard-won, which is precisely what makes it believable and durable.

Rhiannon is wary of Xaden because his divided loyalties place Violet—and every rider around them—in structural danger. Unlike Violet, she does not extend him blind faith, and her skepticism acts as a narrative counterweight to Violet's love. Her caution is principled: she identifies the legitimate risks his double allegiance creates at a time when Violet struggles to maintain objectivity.

Rhiannon demonstrates both bravery and strategic thinking during the combat sequences at Aretia, fighting with clarity under intense pressure. Her performance confirms that her place in the rebellion's inner circle is based on capability as much as personal loyalty. She also excels in Basgiath's deadly training exercises throughout the year, consistently proving herself one of the most reliable cadets in her squad.

Rhiannon protects Violet by insisting she be treated as someone capable of handling the truth, while Dain shields Violet through paternalistic control of her knowledge. This contrast sets out two competing visions of loyalty: Rhiannon demands transparency and respects Violet's autonomy, whereas Dain prioritizes a comfort that ultimately undermines Violet's agency. Yarros uses the comparison as a quiet study in what genuine friendship actually requires.

Liam's death in Fourth Wing casts a long shadow over Rhiannon's arc in Iron Flame, reinforcing for her the mortal stakes of the secrets being kept from riders. His absence deepens the moral weight of her anger at Violet—Rhiannon's fury is not merely personal but reflects every rider deprived of knowledge that could have shaped their choices, making Liam's loss a recurring reminder of what concealment truly costs.

Rhiannon watches Aaric's arrival with characteristic perceptiveness, quietly noting her observations about the mysterious new cadet and factoring his presence into her ongoing assessment of who can be trusted. Her careful scrutiny of Aaric illustrates her intelligence in real time and serves as a consistent reminder throughout Iron Flame that she is rarely caught off guard by people or situations others overlook.