Continue:
Hold I + II and press Run at the "Game Over" screen.
Extra lives:
Stand at least five block lengths away from a lamp post,
then jump while kicking to hit the post perfectly.
Hidden level warps:
Locate the brick bridge on level 1-4B. Kick the right corner
of the bridge and underneath. This will allow game play
to continue in fields 2, 3, or 4.
Locate the area halfway through level 3-3B where two rats
begin to follow your character. Jump on top of them to
reach the two bricks, then jump up. Game play will resume at 6-4.