The Denver Onyx are a founding member of Women’s Elite Rugby (WER), based in the Glendale in Denver, Colorado. The team was founded in January 2025, and competed in the inaugural WER season that year.

The Denver Onyx played their first ever professional game on 29th March, 2025 against the Bay Breakers. The Onyx play their home games out of Infinity Park, the former home of the American Raptors.