TESTAMENT has confirmed the release of its new album "Para Bellum", which dropped in October 2025 via Nuclear Blast. The record was recorded with Juan Urteaga and mixed by Jens Bogren for the first time. The album's cover art was painted by Eliran Kantor.

The band has also announced the official music video for the track "Infanticide A.I.", directed by Joey Durango. The release coincided with the August 2025 announcement of the album.

Chuck Billy has published his memoir, "Holding My Breath: The Two Testaments Of Chuck Billy", set for release on November 10, 2026 through Permuted Press. Co-written with Dave Erickson, the book features a foreword by Rob Halford of JUDAS PRIEST and an afterword by Randy Blythe of LAMB OF GOD.

The memoir is divided into two parts: an "Old Testament" detailing the formation of TESTAMENT and the early days of Bay Area thrash metal, and a "New Testament" that explores Billy's cancer diagnosis at age 38, his Native American and Mexican-American heritage, spiritual healing practices, and his deep connection to the metal community.