Sonic Heroes E3 version for the Microsoft Xbox was the first public demo of Sonic Heroes, displayed during E3 2003.
- The title screen is very different from the final (and similar to the 10.8 prototype).
- The loading screen with the 3 formation rings is used everywhere throughout and is even used in place of the Title Cards.
- Only team Sonic is available in this prototype.
- Two stages (Seaside Hill and Rail Canyon) are playable.
- There are minor differences in the object layout placed in each level, they seem to be present to introduce you to the game hence there isn't a tutorial.
- Rings are awkward in this prototype, they will change spin direction, the texture isn't perfect and has an awkward bump in the model.
- There are no level ups.
- Passing a checkpoint gives you an item. If you pass the gate with Sonic, you'll get Speed Boots. If you pass with Knuckles you'll get a shield etc.
- There is no spoken dialogue and the hints given are simply text with a blue backdrop.
- The camera for the end level cutscene goes all wonky at the end of the level, panning away from Team Sonic.
- After beating the level a "Coming Soon" screen appears and then the game resets.
- Cheese the chao has a texture file contained in playmodel, where the .one, anm and dff archives are contained, it is strangely written in capitals unlike all the other texture files in the folder. It can be opened, however cheese's .one archive (where the txd is in the final) cannot.