Grand Adventure follows the adventures of Luffy and his friends on their search for the treasure called One Piece. The demo on the E3 show floor gives a basic idea of how the game will play out. There are multiple game modes, but the one I got to try (and is the main mode of the game) is the solo Adventure mode. Here you'll actually be put out to sea where you get to control a ship and move it to whatever area you want. There, you'll be given a mission to accomplish before time runs out (or before you're defeated). Some of the missions require you only to defeat your opponent before time runs out, while other missions play more like mini-games. One of these I got to try out was a racing game of sorts. Using an unknown creature (or at least it was one that I didn't recognize), you had to jump and boost your way to the finish line.

The gameplay (fighting) is similar to that of Grand Battle. You play in fully 3D environment with complete control over where you go. There are objects laying around that you can use to pick up and throw at your enemy. Of course, each character also has their own set of crazy moves. On the graphical side of things, it wasn't looking so hot. There wasn't much detail that I could see (especially in the stages I played), and what you could see was pretty painful. The jaggies were extremely evident, though this shouldn't be as apparent on standard definition televisions.

Still, the game looked fairly complete and you can expect it to hit the GameCube in the Fall of this year.