SD 히어로

Hero select:
Pause game play, then press Up, Down, Left, Right, B(2), A(2). The game will resume to confirm correct code entry. Press Select to change your hero.

Alternately, pause game play then press Up, Right, Down, Left, B(2), A(2). Press Select during game play to change your hero.

Easy difficulty:
Hold Down + A and press Start at the title screen.

Hard difficulty:

Hold B and press Start at the title screen.

출처 : http://www.gamewinners.com/nes/SDHeroSoukessen.htm