In Megaman battle network 5 were do you fight bass v1?

He's in Nebula Area. You have to collect all the normal and megachips, and then defeat the DS navis in the final area between a certain time. Beat them too slowly, and you'll fight Nebula Gray Alpha (you fight him the first time you get there no matter what; future times are Nebby G Beta), too quickly and you fight dark Mega. If you get it just right, and you've already fought Nebby G Alpha, Bass will appear and challenge Mega. Beat him, jack out, jack back in, and go back to the place again, and then if you search the area eventually you will run into a random battle with Bass Omega. Kill him to get the Bass emblem which will allow you to fight Nebby G Omega (back at the Darkchip factory where you fought the original).