Suggested by Sonic Sephiria is a pretty solid swordswoman and her speed is what will really help her in this fight. Having regeneration doesn’t hurt either. What this will boil down to though is whether or not she can overwhelm Serah’s plethora of spells and her grand summon. I’m just not sure Sephiria will be able to do it. The deck is stacked against her here. It’s why they say no matter how well tuned your skill is, you’ll want to have more abilities at the ready when you get into a fight. She’s just not ready to take Serah down this time. She won’t be put into a position to really use her sword skills. Serah wins.