Are you fucking kidding me? Dark Gaia is the easiest final boss in videogame history, getting hit? ARE YOU SERIOUS? CAN YOU EVEN USE THE DISSOLVE ABILITY? You don't need Herbs for this fight, the notion is ridiculous. Stand at the bottom, fire your Firebird straight up, dissolve when the indestructible orbs come at you. Repeat until dead.
130°
30°
10°
20°
30°
Ad 
40°
Stand at the bottom, fire your Firebird straight up, dissolve when the indestructible orbs come at you. Repeat until dead.
Jesus christ, GURL GAMERZ.
Jesus christ, KIDS
On another note, wonder if she met the hidden boss from the first game Soul Blazer.