Viruses can modulate microbial methane metabolism (MM) depending on their habitat. Researchers analyzed 982 metagenomes from environments with MM genes and identified 24 auxiliary metabolic genes (AMGs) encoded by viruses, including seven exclusive to MM pathways. These AMGs were found on 911 viral contigs, mostly from rumen viruses. Environmental habitats had fewer such genes. In Vrana Lake sediments, diverse viral communities were found, with some encoding 13 AMGs that could modulate host metabolism, though none directly participated in MM. The study suggests that viral use of AMGs to modulate MM varies by habitat and is not predictable by biogeochemical properties. Viruses may influence MM by encoding genes involved in methane oxidation and production, such as pmoC, mtrA, and others. Some viruses encode genes like bfr, which may affect iron metabolism in methanogens. The study highlights the potential of viruses to impact MM, emphasizing the need for further research into viral contributions to methane cycling and climate change.Viruses can modulate microbial methane metabolism (MM) depending on their habitat. Researchers analyzed 982 metagenomes from environments with MM genes and identified 24 auxiliary metabolic genes (AMGs) encoded by viruses, including seven exclusive to MM pathways. These AMGs were found on 911 viral contigs, mostly from rumen viruses. Environmental habitats had fewer such genes. In Vrana Lake sediments, diverse viral communities were found, with some encoding 13 AMGs that could modulate host metabolism, though none directly participated in MM. The study suggests that viral use of AMGs to modulate MM varies by habitat and is not predictable by biogeochemical properties. Viruses may influence MM by encoding genes involved in methane oxidation and production, such as pmoC, mtrA, and others. Some viruses encode genes like bfr, which may affect iron metabolism in methanogens. The study highlights the potential of viruses to impact MM, emphasizing the need for further research into viral contributions to methane cycling and climate change.