I couldn't finish 'em. Looks like this's gonna get complicated.
The Boss Gobby will order the Minion Gobbies to attack. As long as Rydia and Luca are in the back row, the damage from the Minion Gobbies should be minimal. The Minion Gobbies will not attack unless the Boss Gobby orders it. Unlike the Boss Gobby, the Minion Gobbies do not counterattack when hit with attacks unless the Boss Gobby is dead. Killing all the Minion Gobbies will cause Boss Gobby to use Protect, Shell, Haste, and Curaga on himself to increase the difficulty of the battle. Killing off two of the Minion Gobbies and leaving one alive will prevent the Boss Gobby from buffing himself, as well as minimize the damage the party receives when Boss Gobby orders the minions to attack.