The Grinwhale is a boss from Grandia. It is encountered in the Pirate Hideout on Pirate Island. The Grinwhale appears alongside Lure which together form the whole monster. The Grinwhale body has the ability to cast Electric Shock, Body Blow and Spew.
The Grinwhale will primarily target Justin using its Lure, using Entice to immediately deliver a strong physical attack. Feena should evade and stay away so she does not get caught by its Body Blow attack and support Justin. Dispatching the Lure part of the boss first helps with minimizing unnecessary damage on Justin.
At times the Grinwhale will try to suck in both party members with a move called Spew which is not really powerful. However, the party should beware of the Grinwhale's Electric Shock which can be rather powerful and affects all party members.
The Grinwhale has a slight weakness to Fire based magic which can be boosted now Gadwin and Sue have left the party. Justin's Lotus Cut can be really effective. If Justin has the Fire Rod equipped, his Combo and Critical attacks will deal extra damage to this enemy, but the damage output of Lotus Cut is not affected by this weapon.