No - I did not want this. Alas, the game had other plans and gave me 7 Summer Fredericks last year (wanted Summer Gaius) and I got an 8th on the free pull. As his spd and def went up a tick this time, I feel like he might actually have usable stats now. But how to build? I'd rather not use up any high value seals (like CD3).
For simplicity, his stats are now : 43 hp / 35 atk / 37 spd / 33 def / 16 res
A spd/atk boosting A and Desperation generally works well.
It's kind of boring to do this with every unit that has 35+ offensive stats, but it's popular for a reason. Frederick can pull it off rather well in any case because he can initiate on a good many bows/DC melee thanks to his good speed, def, and HP.
I'm assuming you score pretty high for Arena / AA.
I wouldn't go for a speedy dagger build when there's dagger units with a much more aggressive stat line. (Like Carrot HB S!Kagero) However, I would recommend using your Frederick as supportive backup AA unit.
Something like refined Smoke Dagger+, Moonbow, Death Blow, Sword/Axe/Lance Breaker and spurs/drives when you're facing against specific armor units that you want to check.
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