Gau has like 2-3 abilities out of that entire move set that are worth using throughout the game. And then some battles like this one Gau has other skills that own.

Gau is the Hunter/Beastmaster class changed a bit. If you played FFV and tried out the Beastmaster Job, it's almost like that. The Veldt is basically, if you want him to learn new beast abilities just send him off, after some time he will come back with some fresh abilities. All monsters in the game eventually make it to the Veldt.

He is used like so. If you are using him on Number024 and you cast Stone...Gau will cast stone or any other abilities under that "Monsters" move set the entire battle or until he has fainted. So if you think about it he's also somewhat of a Berserker as well, but only because you can't choose something else after you chose one.


Edit: Also Gau is by no means the best character in FFVI. I just like him because he's very unique. As well as Setzer.