Level Passwords

Password Effect
MWTV .... Level 2
KVSW .... Level 3
KVMW .... Level 4
RQNJ .... Level 5
VKX4 .... Level 6
NZ1N .... Level 7
Z66F .... Level 8

Unlockables
Obtain Musya Blade

To obtain the Musya Blade, you must choose to spare Xephial's life (the third boss). Afterwards, backtrack to level one via the overworld and talk to Musya's brother. You will then be asked to defeat him in combat. Do so (he is very hard) and you will obtain the Musya Blade. The Musya Blade is the strongest weapon in the game.