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Megakaryocytes in myelofibrosis show marked atypia and pleomorphism and are typically increased in number, forming dense clusters or cohesive sheets, often in paratrabecular, peri-sinusoidal, and intra-sinusoidal locations. They exhibit a high nuclear-to-cytoplasmic ratio with disorganized morphology, including distorted, elongated, and angular cell shapes. There is significant variation in size, ranging from small forms with scant cytoplasm to larger atypical cells, with frequent presence of bare nuclei. Nuclear features are characteristic and include poor lobation, hyperchromasia, irregular folding, and pyknotic chromatin rather than orderly multilobation. Overall, these dysplastic megakaryocytes are a key feature of myelofibrosis and are typically seen in association with progressive reticulin and collagen fibrosis within the bone marrow.