Brument, HugoPodkosova, IanaRatschiller, GabrielVailland, DamienKaufmann, HannesJorge, Joaquim A.Sakata, Nobuchika2025-11-262025-11-262025978-3-03868-278-31727-530Xhttps://doi.org/10.2312/egve.20251356https://diglib.eg.org/handle/10.2312/egve20251356The user's perception in Virtual Reality (VR) with avatars is strongly influenced by the Sense of Embodiment (SoE) and Sense of Agency (SoA). However, traditional VR interfaces often rely on human-centric interactions (e.g., hand or raycast) that may not translate well to dissimilar avatars that differ from human anatomy. This paper describes the design and evaluation of selection and navigation metaphors in VR for a dissimilar avatar. We introduce StretchIK, an adaptation of the Forward Backward Reaching Inverse Kinematics that works with non-isomorphic interaction metaphors. We conducted two user studies to investigate the influence of the interaction metaphors on users' SoE and SoA. In the first study, we compared two selection metaphors (Go-go versus Head-Selection), where participants had to grab virtual cabbages. In the second study, we compared two navigation metaphors (3D steering versus 3D Leaning), where participants had to travel through virtual rings. The results showed that users had a good SoE in the dissimilar avatar for interacting. However, the interaction metaphors affected users' performance, SoA, where Go-Go outperformed Head-Selection, and 3D steering outperformed 3D Leaning. Our results could improve interaction with dissimilar avatars, eliciting potential future work regarding shared control of dissimilar avatars in VR.Attribution 4.0 International LicenseCCS Concepts: Human-centered computing → Virtual reality; User studiesHuman centered computing → Virtual realityUser studiesInfluence of Non-Isomorphic Interactions on Users' Agency with a Dissimilar Avatar in Virtual Reality10.2312/egve.2025135610 pages