The answer to your question.
Suggested Rages for Gau to learn at the Veldt.
Anguiform (uses Aqua Rake and absorbs Water)
Aspik (has Auto-Float and uses Giga Volt, which is a very powerful lightning-Elemental attack. It's stronger than any Level 2 spell)
Primordite (uses Numblade , which causes Stop, similar to the Areneid , but has different elemental and status properties)
Gabbldegak (casts Vanish)
Harvester (has Auto-Float, auto-Haste, and casts Haste)
HadesGigas (uses Magnitude8 )
SlamDancer (casts Ice 2, similar to the Dark Side, but has different elemental and status properties)