patch2.cpk is a CPK archive only available from PSN as a day-one update patch for both Persona 3 Dancing Moon Night and Persona 5 Dancing Star Night. It is identical for both versions and contains a lot of data pertaining to DLC characters and fields. Below is a list of changes:
The field model for the top of Tartarus, as well as dance animations for Labrys and Ken (for P3) and Ren, Morgana, Ann, Futaba, and Lavenza (for P5) along with a newer version of Ryuji's swimwear model.
msg.bin has been updated.
The background for a song has been added (bg_214.tga), and the init and commu bin files have been updated.
The staff_P5D.bin has been updated.