Zanac Codes and Cheats

Level Select: Want to jump immediately to any of the first ten levels? Press the Reset button on the NES 13 times, then press Select on the controller. Change the level number with the arrow pad, then press Start to play your slected level.
(haven't been able to get it to work, will keep trying)

Sound test mode: To enter the sound test mode hold down buttons A and B simultaneously before turning on the power. Then release both buttons and check the sounds!
(this works for sure)

Continue in Area 11 and 12: To keep going after your ships are depleted in the 11th and 12th areas do the following. When your game is over set the ship to "Continue" on the titlescreen. On controller 2 press Down, then Up. Now press Start on controller 1.
(haven't even gotten to those levels, can't test)

Mega Ship and 1-UP: To make your ship a super plane press and hold A and B while pressing START on the title screen. Once you get your 6th powerup, you will have a 1-UP party-everything you see will transform into a 1-UP!
(for sure you can change the ship type, still need to gest the other part)