Silent Avalanche is the name given to several different elite squads of extremely powerful Normals serving the Bernard and Felix Foundation in Armored Core 4 and Armored Core: For Answer. The guardians of BFF prized Sphere Kojima energy facility, Silent Avalance is the main force that protects and defends this facility. They are notorious in Armored Core 4 as having beat back any attacks by the other companies. These soldiers pilots variations of BFF's 044AC called 048AC-S and are all white Normals designed specifically for combat in the ice floes. In the events of Armored Core 4, the Silent Avalanche squad had a reputation for being stronger than many NEXTs, as they were able to defend against all forces that attempted to invade the facility before they were eventually defeated by Anatolia's Mercenary.
Their cannons have even longer range and greater power; combined with their camoflauge, this makes Silent Avalanche extremely effective snipers.
They're defeated by The Raven in Armored Core 4 for the first time during the homonymous mission.
They also appear in Armored Core: For Answer in the missions "Defeat Silent Avalanche" and in the Hard Mode version of "Defend Anti-Satellite Cannons", where they fight alongside BFF Lynx Lilium Wolcott and Wong Shao-Lung.