Enterococcus faecalis, a non-oral nosocomial pathogen, intriguingly ranks among the most frequently retrieved species from polymicrobial infections of dental root canals. This review integrates findings from the latest omics approaches, alongside emerging evidence of E. faecalis interactions within oral polymicrobial communities, to refine our understanding of its role in these infections. Herein, E. faecalis emerges as an ecologically invasive species and a catalyst of the pathogenicity of entire communities.