Update 1.06.1 does not add new parts. It does not add new missions. It fixes the math . The official patch notes emphasize "adjustments to weapon parameters to expand build diversity," which is developer-speak for "we are nerfing the bullies."
While 1.06.1 was a small fix, it sits on top of the significant changes introduced in the base (February 6, 2024), which included:
Armored Core VI Fires of Rubicon Update 1.06.1: Refining the Rubicon Battlefield