Introduction: Pheochromocytomas and paragangliomas (PPGL) are rare neuroendocrine tumors with high heritability. While most are benign, approximately 25% are malignant, defined by distant metastases. Molecular classification has identified three clusters, with Cluster 3 (Wnt-signaling) being exclusively somatic and associated with aggressive behavior. We report a rare case of metastatic malignant pheochromocytoma driven by a somatic DNMT3A mutation, highlighting its unique imaging characteristics and rapid clinical progression. Case: A 55-year-old female presented with paroxysmal hypertension, headache, and a 10-kg weight loss. Biochemical workup revealed markedly elevated 24-hour urine metanephrines (163 × ULN) and normetanephrines (47 × ULN). Imaging confirmed a 15-cm left adrenal mass with liver and widespread skeletal metastases. Functional imaging demonstrated a striking mixed avidity: liver metastases were predominantly fluorodeoxyglucoseavid (SUVmax 7.0), skeletal lesions showed high Ga-68 DOTATATE avidity (SUVmax 6.9), and the primary tumor exhibited the strongest avidity on 131 I-MIBG scan. Whole Exome Sequencing identified a rare pathogenic somatic variant in the DNMT3A gene (c.2645G>A) with no other germline or somatic mutations in known susceptibility genes. Despite adequate alpha-blockade and supportive care, the patient developed acute liver failure and coagulopathy, rendering her unfit for any form of invasive intervention and finally succumbing to the disease within 3 months of presentation. Conclusion This case underscores the aggressive nature of Cluster 3 PPGLs associated with DNMT3A mutations, which likely promote tumorigenesis via Wnt-pathway activation and epigenetic dysregulation. The discordant functional imaging reflects significant tumor heterogeneity, which may complicate diagnostic and therapeutic strategies. Given the rarity of DNMT3A-mutated PPGL (<1% of cases), this case report emphasizes the necessity of comprehensive molecular profiling in advanced disease to refine risk stratification and guide the development of precisionbased palliative management in rapidly progressive cases.