Takeshi no Chousenjou Cheats

If your energy gets drained, press the A and B buttons at the same time 3 times in a row. If done right, your character should get back up with full energy.

At the password screen, press Left 2 times, Down 2 times and enter the Japanese character. Then Up 1 time, Right 1 time and enter the Japanese character. Now repeat that same pair of Japanese characters 8 more times. Then for the final two characters, press Up 1 time, Left 6 times and enter the Japanese character. Right 6 times, Down 1 time and enter the Japanese character. Hit "End" to start on the Pacific Island.

At the password screen, press Down 1 time and enter the Japanese character 20 times. Now hit "End" and you'll start in a Jungle. Go left, enter the hut and leave it right away. You'll now be in a different area. Go left again to enter a jungle. Start counting the trees and hold Up in the middle of the 16th & 17th tree. If done right, you'll enter a secret area with a Japanese soldier.