in eggmans base go to the bottom floor (the circular area) keep on walkin around the circle and eventuly a big platform will stop you. go on top of the platform and pick up the guy. go up stairs and place him next to metal sonic.
There isn't a mission mode in sonic adventure.Only on Sonic Adventure DX.
But you can play metal sonic.
Mission Street is a stage in Sonic Adventure 2 played by Tails, Sonic can...
he is in a mission mode in sonic rush
Metal Sonic doesn't get a story in Sonic Adventure however you can play him in trial mode to unlock him get all the emblems you can go to every level Sonic goes to as Metal Sonic you can even fight the bosses and play the minigames.
in sonic adventure dx you can only unlock metal sonic by collecting 130 sonic emblems.
u can be him in 2 player in sonic adventure 2 battle
yes their is a cheat code that enables play of metal sonic in levels even a gold metal sonic
When you get all 130 emblems you can play as metal sonic on trial.
The second fight between sonic and shadow is a good one, or mission B for shadow's city mission.
No, Not officcially.But There is a Neo Metal Sonic Hack On Sonic Adventure DX: Directors Cut For The Pc. http://www.youtube.com/watch?v=9ZdqelxQiTw
If you have beaten all the missions on Sonic Adventure DX all of the missions become replayable whenever you enter Mission mode. This is most likely happening to you.