A new Natal title for Xbox 360, developed in-house at Microsoft, has been revealed by a US movie director this week.

The new game is, as we have come to expect, firmly in the 'casual' gaming category, so is likely to get hardcore gamers any more excited about the prospect of motion controlled gaming on the Xbox 360 later this year.

River Rush was detailed on the blog of US movie exec James Gunn, who wrote about his recent experiences at a Microsoft showcase.

Aerobically-challenging game

Gunn played both the already-announced Ricochet, and the previously-unannounced River Rush alongside a friend of his from Microsoft.

Gunn described the new Natal tile as follows: "It's a game where you stand side by side in a river raft, so it's two people playing at once. To move right, you have to step right; to move left, you have to step left. As you rush down right rapids, you have to jump up and slap floating stars in the air - the whole raft jumps up every time you do.

"This game was even more exhilarating than the kicking one, and even more aerobically challenging. In fact, I'd say the ONLY drawback to the Natal some people may have is that you have to get up off your ass to play it. But, for me, a person who likes exercise and gaming, it's sort of a dream come true. An hour of playing Natal every night will definitely burn calories."

Via James Gunn blog