We recommend using methylation profiling whenever feasible, Olig2 and p53 staining in delineating differential diagnoses of poorly differentiated embryonal-like tumors of the cerebellum, in addition to the usual tools to differentiate other embryonal tumors like ATRT (atypical teratoid/rhabdoid tumor) and ETMR (embryonal tumor with multilayered rosettes). The gene discussed is OLIG2; the disease is rhabdoid tumor.