If you want legal alternatives, here are safe options:

If you find a download labeled "Mortal Kombat 9 PSP ISO," it is typically one of the following: Fan-Made Mods

Improved, higher-resolution textures for character models to make them look closer to the 2011 console release.

While you can play on a custom-firmware enabled PSP, using the PPSSPP emulator on Android, PC, or iOS is often recommended for better graphics and performance.

: This is the official PSP release based on Mortal Kombat: Deception . It is widely considered the best native fighting experience on the platform, featuring exclusive content like Endurance Mode and a massive roster including Shao Kahn and Goro. Key Features of High-Quality MK9 Mods

If you are downloading a fan-made "high-quality" ISO for the PPSSPP emulator, look for these specific features that define a premium mod:

Downloading ISO files from third-party sources comes with several risks, including: