Traditionally, the communication of cultural heritage has relied on oral and written narratives. In the digital realm, informative and interpretive narratives for cultural heritage are delivered in various ways, with applications serving as virtual guides (VGs). These range from neutral, impersonal system narratives to engaging, role-playing VGs. The latter are widely utilized in commercial contexts for the communication and promotion of cultural heritage. While Non-Immersive Virtual Reality (N-IVR) applications predominantly employ VGs, their use in Immersive Virtual Reality (IVR) and Immersive Augmented Reality (IAR) applications is significantly less. Considering the interpretative significance of narration for a digital heritage experience, this study focuses on the use of VGs in immersive XR experiences from the perspective of narrative design. It critically reviews selected existing approaches to VGs in XR for heritage, aiming to deepen our understanding of the current state of interactive narrative design in this context.