User blog comment:Mckrongs/July 14 2010 - New Famitsu MHP3 Scans!/@comment-111.95.130.164-20100816111642/@comment-190.27.178.109-20100825225205

The PSP memory, processor speed, storage space, its much much less than a Wii. If they added everything necessary for underwater areas and battles, they would had to remove in game content (armors, weapons, monsters...)