Find the man selling Morph potions north of the town. Purchase a Morph potion for 100 gold and drink it. Then, stay on the same screen, wait until Kilgaly morphs into "Link" and enter one of the following codes:
Ksiamgod: 4 spells
ksgiveme: max money
ksliveitup: max HP
ksbadpower: max MP
kswoahbaby: max attack
kslensboy: kilgaly encased in a bubble
kschicken: no fights on field
kslifesucks: suicide
ksitstoeasy: quit game