Go to the title screen and press Circle, X, Triangle, Square, Square, Circle, Triangle.
Easy experience
Some locations will respawn monsters. Move back over areas already traveled to encounter them again.
Eternal Blade
To get the game's ultimate weapon, you must go through the second cave on the beach when the game starts. The only way to open the door is to cast a spell on it using an attack ring. Inside is a teleporter. Make sure to get plenty of healing items before entering the first teleporter, as you must go through four different levels of mayhem. Defeat the final Boss on the fourth level to get the Eternal Blade.
Get your short sword back
At the start of the game, go back outside the cave and kill the crab-like things. Then, collect the gems they leave. Collect 8 on the way to the military camp. After the man takes your sword for safe keeping, talk to Wallace and he will give you a knife. Talk to him again and he will sell you a sword for 8 gems. Do so, as you can regain the gems easily. This is very helpful when in the water temple. Go to the warehouse after the houses in the research camp are done burning. Your sword will be lying on the floor in the back.
Pause game play
Press Select to pause game play.
Reach The Cave
When you start off in the tunnel, turn around go outside. Go to the right side of the beach. Get close to shore, then walk in the cave on the other side.
Saving Magic Stones
Do not waste your Magic Stones early in the game. Save them for later, when you will be fighting very strong creatures after the Iron Mill.
The Secret Dungeon
Best Place to Get Invulnerbility and Max XP. There is a hidden four-floored dungeon in this game. To go there, you need a Dark or Light Magic Spell Ring. Go to the beach where you start the game, go to the left and you'll find a door that is locked. Cast a Dark or Light Spell on the door, and it should open. Inside this dungeon, you'll find some pretty hard monsters. They can kill you in one hit, so be very careful. There are Lvl 5 Magical Stones of all kind, Magic Rings (in the 3rd floor, there is a bird that give them infinitely), Special Rings (including the Mirage Edge, that makes you hit 4 times instead of one), and the Eternal Sword (you have to kill a monster in the last floor to get it). This is also a great way to gain tons of XP. The best way is to kill the big birds in 2nd floor. The best way to kill these birds is to get Dragon Fangs by killing the white crabs on the 4th floor. Every time you kill them, they'll drop a Dragon Fang that will raise your stats by one. Keep using these until all your stats reach 255, and you'll be strong enough to never die.
Cheat mode...