Instructions
Play through the game until you reach the boss fight with the Ghost of Ladon. He is invulnerable when his hands are out in front of him, so wait for him to put his head down before attacking. Dodge out of the way after this attack, then go back in and attack him again once his hands are down.
Move up or down to avoid Ladon's fireball attack. He will use this whenever you get more than three or four spaces in front of him. Ladon will also use an attack where he disappears entirely from the screen. Immediately move either one space up or one space down when this happens, as this is his signal for a charge attack that will hurt you for at least 1,000 damage if it connects.
Use "HP Pots" to restore health whenever you take damage. The Ghost of Ladon can take away a lot of your health in one blow, so it's best to always be close to your maximum health. Continue attacking, then retreating from the Ghost of Ladon until he is defeated.