Press Up + A + B at the tile screen. (A tone confirms correct entry.)
Pause game and press A, B (x2), A (x2), B (x2), A.
Wall, What Wall?
On level 3 (the city) take the elevators up at the begining of the level. DO NOT GO ON THE TOP FLOOR! Instead jump of the elevators a little early and towards the wall on the left side. If you keep holding left on the D-Pad you should go through the wall. This lets you skip about half of the level and is much more easier.
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