Ensure you have part1.rar and part2.rar in the same directory.
You may need a separate "Update" NSP to reach the latest version (e.g., Ver. 12.0.0) for online play or Sunbreak compatibility. MONSTER HUNTER RISE (NSP)(JP)(Base Game).part2.rar
Right-click Part 1 and select "Extract Here." Ensure you have part1
You can team up with up to four players in a Lobby. MONSTER HUNTER RISE (NSP)(JP)(Base Game).part2.rar
The software will automatically pull data from Part 2 to create a single .nsp file.