Abstract: Super Typhoon Ragasa experienced anomalous intensity changes, characterized by offshore rapid intensification (RI) and nearshore intense typhoon maintenance (Near LF). This study focuses on analyzing the associated inner core structural characteristics and the evolution of the typhoon intensification index (TCII) to reveal the causes of these anomalous intensity changes. By examining the vortex geometric properties, inner core thermodynamic and dynamic features, and external environmental conditions related to the intensity anomalies, we find that, compared with the Pre RI period, the RI and Near LF stages are characterized by a significant contraction in horizontal scale, a more upright vertical vortex structure, reduced asymmetry, enhanced low level relative vorticity and radial gradient of equivalent potential temperature, and increased Rossby number Ro. However, during the pre landfall Near LF stage, the asymmetry increases. Using composite indices that incorporate these indicative factors and can comprehensively represent typhoon anomalies—namely the Y index, Rossby number Ro, and typhoon intensification index TCII—our calculations show that TCII effectively captures the intensity anomalies during both the RI and near LF stages. The increase in the Y index is the dominant factor driving the rise in TCII and the onset of RI / maintenance of the intense typhoon during near LF. As asymmetry intensifies before landfall, the contribution of the Y index decreases, while the contributions of changes in typhoon size and rotational kinetic energy become substantially more important. Further analyses of ventilation effects in a shear relative coordinate system, mid level moistening, and momentum budgets are conducted to reveal the physical causes of the intensity anomalies. The down shear (DS) and left of shear (LS) quadrants are identified as the preferential sectors for intensification. Before RI, notable positive low level ventilation (warm and moist anomalous inflow) occurs in the DS quadrant, and during RI, mid level moistening is also evident in the DS quadrant. During the Near LF stage, positive low level ventilation and mid level moistening in the LS quadrant play key roles on sustaining the nearshore intense typhoon. During the RI period, the tangential wind acceleration is primarily driven by the mean radial vorticity flux, while the radial wind adjusts under gradient wind balance constraints. Before landfall, the momentum budget processes manifest as maintenance and redistribution of the strong inner core. Together, these processes constitute the internal dynamic adjustment mechanisms responsible for Ragasa''s offshore rapid intensification and nearshore maintenance.