We've not completely sussed out how this works yet, but it appears that player can nurture helpful creatures on their portable VMS units and then use them in the main Sonic Adventure game. At first there is only one stage open to Sonic. Having seen Tails crash his plane, Sonic sets out to rescue him and you're thrown into the first level which is based on the familiar Emerald Valley theme. Well, this is the 3D equivalent. Sonic blasts around some sections of the courses at incredible speeds with the terrain moving at a smooth frame-rate.
Graphical detail is stunning.
There's one section where a massive whale dives out of the water and breaks up the terrain Sonic is running over. There are also some beautifully modelled dolphins which jump over the play area and even little touches like Sonic leaving footprints in the sand. By the time you complete this first stage, Sonic Adventure 's visual credentials have impressed. The game is displayed in crisp high-resolution with very detailed scenery which draws a long way into the distance. As you'd imagine, it's much more impressive than anything you'll see on the older N64 and Playstation hardware.