Downloading Mortal Kombat vs. DC Universe from unauthorized third-party websites constitutes piracy, which is illegal. The only legal way to obtain the game files required for RPCS3 is to from a physical Blu-ray disc that you legally own. This process involves using a compatible Blu-ray drive on your PC and specific software (like ImgBurn or the PS3 Disc Dumper) to create an ISO or folder structure that the emulator can read.
Mortal Kombat vs. DC Universe on RPCS3: Complete Download & Setup Guide mortal kombat vs dc universe rpcs3 download