Game supports one- and two-button joysticks.
TRIVIA: The Japanese title PC Genjin is actually a play on words, rhyming with 'PC ENGINE' and translates to "primitive man".
Based on 1989 PC Engine release, PC GENJIN (aka BONK'S ADVENTURE outside Japan).
Select ‘OPTIONS’ from the title screen. On the option screen, use and enter the following sequence:
UP, UP, DOWN, DOWN, LEFT, RIGHT, LEFT, RIGHT
Now start the game and infinite lives are yours.
Jump up and turn on the autofire on your joystick. You’ll glide through the air while spinning madly. This should help you dodge all the dinosaurs and valcanoes.