Sega has announced Phantasy Star Eternal Hunters and.. I'm not quite sure what to make of it. Players must register for Eternal Hunters using Mobage Town. (Which had a previous collaboration with Phantasy Star portable 2, it's a mobile portal) It's being described as a local interlocking rpg which utilizes GPS information on the phone. 30,000 people will be invited for the initial test if you register at the site.
You will handle top secret missions of various things in the real world like going out finding various data and battling various monsters. These events require players to go about Japan, but within the game they will happen on an "unknown planet." Of the players who participate they can receive a special item for Phantasy Star Portable 2 Infinity.
The details on the battle system and characters will be revealed at a later time.