How does Swift Sparrow affect Sylgr?

Still counts towards Sylgr's effect. Great choice for Ylgr's A slot.

I'm pretty sure it only takes base stats + visible buffs into account. The description for Swift Sparrow mentions 'during battle' while Sylgr mentions 'at the start of combat'. (A similar interaction also occurs with Kliff's Sagittae where Death Blow and other skills that boost Atk in combat don't count toward his weapon's requirement, meaning that he could still get the +5 to all stats despite possibly having more Atk after such skills were taken into account, as long as his visible Atk was lower than his opponent's by 5.)

Doesn’t work unfortunately. It’s basically Kliff’s weapon so in-combat buffs don’t help activate the condition while visible buffs will.