[Rockard]

http://www.youtube.com/watch?v=bflYBp-YV64&search=famicom%20disk

1:16 into the video.

2 player rpg, it looks like. Does anybody recognize this game?
If i didn't know seiken densetsu for famicom disk never was developed, I would swear this was the game.

[KingMike]

It's Radia Senki by Tecmo. Fan-translated as Chronicle of the Radia War. Supposedly, it was at one point meant to be officially translated as Tower of Radia, but that translation never came out. Only the Japanese original.
It's actually only a 1-player game. Only the main character is directly controllable. The other party members are controlled by the kinda stupid AI.
The game's actually more like a spiritual ancestor to Star Ocean (at least battle-wise). You can direct the other players to move somewhere or attack enemies. And enemies will just suddenly appear on the main screen, at which point you can move the main character and attack as you wish, but you can't leave the screen (which creates another AI issue, party members will get stuck behind walls, and you'll have to use the "move to" command to direct them around each corner (or forget about them if their help is not worth the trouble). That's probably why the SO creators at least switch to an empty arena for combat.