If you own a physical cartridge or bought digitally:
You cannot install just the DLC NSPs. The DLC requires Update v1.3.0 or higher and the "Unlocker" NSPs. If you install a DLC NSP without the corresponding title update, the game will ignore it.
: Major patches, such as the June and July Updates , have fixed various progression blockers in levels like "Hell Base" and improved UI readability for handheld mode. DLC & Seasonal Content
If you own a physical cartridge or bought digitally:
You cannot install just the DLC NSPs. The DLC requires Update v1.3.0 or higher and the "Unlocker" NSPs. If you install a DLC NSP without the corresponding title update, the game will ignore it.
: Major patches, such as the June and July Updates , have fixed various progression blockers in levels like "Hell Base" and improved UI readability for handheld mode. DLC & Seasonal Content