Do your worst, you freak!Sazh
Brynhildr inflicts Doom on Sazh at the beginning of the battle, and instead of defeating her, Sazh must fully fill up her Gestalt bar.
Sazh should prioritize applying Haste and Enfrost to himself, and can apply Vigilance to both himself and Vanille to stave off knockback. Vanille's offensive spells and curing benefit from Haste and Faith.
Thanks to conditional chaining modifiers, the gestalt gauge will fill very quickly if Sazh queues up Attack>Blitz, with his Blitz greatly benefiting from Enfrost and the alternating ability bonus.
Sazh can use a shroud before he meets up with Vanille, but will still need to cast Enfrost manually.
Brynhildr is a Shieldmaiden and a Valkyrie in Norse mythology. In the Völsunga saga, she was sent by Odin to decide a fight between two kings, but was punished by the god after helping his least-favored one then banished her to the top of mount Hindarfjall in the Alps. She must sleep within a ring of fire until any man rescues and marries her. Sigurd entered the castle and awoke Brynhildr by removing her helmet and cutting off her chainmail armor.
The two fell in love and Sigurd proposed to her with the magic ring Andvaranaut. She appears as a main character in the Völsunga saga and some Eddic poems treating the same events. Under the name Brünnhilde, she appears in the Nibelungenlied and therefore also in Richard Wagner's opera cycle Der Ring des Nibelungen.