Enter Player01 or Player02 as a password, with the remaining password locations filled with + or - characters.
In Front of The Last Boss Door
At the password screen carefully enter the following password:
cHR0(zero)EScxgoAq
iky7ihO(letter)feBGe
Invincible player two
Enter any valid password for player one, then enter KKKKKKKKKKKKKKKKKKKKKKKK as a password for player two.
Level 22 (Final Boss)
Enter YNzYSMChriGIgLV-ihOdfCGe as a password.
Level 22 (Start)
Enter 2R3KD4RG0J9D3YT0664LJ as a password.
Level 45 character
Start a new game in one or two player mode and select a dungeon. Immediately press Run when game play begins to display the current password. Replace characters 10 through 14 in a one player password with "NNNb". For a two player password, replace characters 34 through 38 with the same sequence. Reset the game and entered the modified password to begin game play.
Pass up enemies
If you reach an enemy that you can not defeat, turn rapidly back and forth while pressing Attack and holding Forward. If done correctly, you will walk right over the enemy.