The Serpent is a boss from Grandia. It is encountered on the top floor of Typhoon Tower. The Serpent appears alongside Hot Head, Mean Head, Bad Head and Nice Head which together form the whole monster. The Serpent body has the ability to cast 4-Head Attack.
Eliminating the heads one by one would probably be the better strategy for weaker to normal leveled parties. Eliminating any one head prevents the Serpent from ever using the 4-Head Attack which can be very dangerous.
Start the battle with Gadwin's Dragon Cut, this will deal a good amount of damage to all foes. Feena can use area-effect spells such as Burnflame, Burnflare, Howlslash. Have Justin use Midair Cut on one of the weaker heads then have him concentrate on defeat each head.
The battle ends either by depleting the bodies HP or destroying all four heads.