After only a day after revealing what "Project K" is - Kekoro RPG, Namco Bandai have put up yet another teaser page for an upcoming RPG. The natural question is whether this is yet another Tales games, I have no idea myself, all that is known is that the page in question features a strange pattern on the background, and the URL contains the phrase "RPG_LOST"

It's a sequel, but to what game? 
  
The teaser page now states "the return of that RPG"

Well what RPG IP does Namco have then, that hasn't had a sequel in a while? It can't be a long list.

I reckon it's a new Tales game 
 
 "Solve a lost mystery," "A new adventure" and "Unknown World." In the background are images of a volcanoes and what looks like a lake.

    

" Well what RPG IP does Namco have then, that hasn't had a sequel in a while? It can't be a long list. "

Digimon Lost Evolution for the Nintendo DS.
 
 http://www.bandaigames.channel.or.jp/list/ds_digimon_lost/
 
Sure was not expecting this.

Wow, who could have.