E-Mail the legendary master Shin.
Put Cipher in the subject and write the password in the body.

Go to mega's menu and press select, then you'll see a blank screen, press the correct blank spots which is coded in letters below. After you transform into one of the forms, you automatically turn into that form you used at the start of the battle, but if you want to turn back into normal Mega Man you have to reset your game.

Open the Wave Command Editor of a Blank card, input the codes below and the Blank cards will becomes the battle cards.

By having the any of the following GBA Games in Slot-2 of the NDS with Ryuusei no Rockman 2:
Battle Network Rockman EXE (Megaman Battle Network)
Battle Network Rockman EXE2 (Megaman Battle Network 2)
Battle Network Rockman EXE3 (Megaman Battle Network 3 White)
Battle Network Rockman EXE3 BLACK (Megaman Battle Network 3 Blue)
Rockman EXE Battle Chip GP (Megaman Battle Chip Challenge)
Rockman EXE4 Tournament Red Sun (Megaman Battle Network 4 Red Sun)
Rockman EXE4 Tournament Blue Moon (Megaman Battle Network 4 Blue Moon)
Rockman EXE4.5 Real Operation
Rockman EXE5 Team of Blues (Megaman Battle Network 5 Team Blues)
Rockman EXE5 Team of Colonel (Megaman Battle Network 5 Team Colonel)
Rockman EXE6 Cyber Beast Greiga (Megaman Battle Network 6 Cybeast Gregar)
Rockman EXE6 Cyber Beast Falzer (Megaman Battle Network 6 Cybeast Falzar)

Accomplish something in-game to recieve these different icons on your New Game/Continue screen. Getting them all will also result something new to appear on the screen when you start your game. You'll also be able to fight the Xa Version of the Final Boss at the end of the game which has 4000 HP once you obtain Rockman [Megaman] Star, S Comp Star, M Comp Star, G Comp Star, and OoPart Star.