Black Knight

Weapon: Alondite(+Eff)

Assist: Positional Assist

Special: Black Luna

Passive A: Atk/Def Unity / Atk/Def Bond 3 or 4 / Atk/Res Unity / Atk/Res Bond 3 or 4 

Passive B: Special Fighter

Passive C: A/D Near Save / A/R Far Save

Sacred Seal: Mystic Boost / Mirror Stance / Atk/Def Bond

• With the addition of Slaying to Alondite, the Black Knight now has access to a 2cd Black Luna which allows him to trigger it instantly when he’s attacked as long as he has a means of increasing his special charge on enemy phase(Options include Special Fighter, Steady Breath, and support from Brave Lucina), and as long as the foe lacks Guard. This makes him an extremely dangerous user of Save skills, since Black Knight can cover for his allies and KO many foes in a single blow with Black Luna, although he should be wary of taking on dragons with Near Save due to his low Resistance.
• Atk/Def Unity and Atk/Def Bond 4 both give Black Knight some added resistance to the ever present visible debuffs, as well as a large boost to Attack and Defense. Their Atk/Res counterparts can be used if one opts for Far Save instead, although Black Knight has much more trouble countering mages without heavy investment due to his poor base Resistance.
• Black Luna is what sets the Black Knight(and Zelgius) apart from other sword armors. Very few units can survive an Attack that cuts 80% of their Defense without damage reduction, and it allows him to make short work of many foes in spite of their high Defense stats.
• Special Fighter grants the Black Knight +1 Special cooldown while inflicting -1 Special cooldown against the foe as long as his HP is above 50%, protecting him from enemy specials while allowing him to trigger Black Luna in a single hit coupled with his refined Alondite’s Slaying effect.
• The Mystic Boost sacred seal gives the Black Knight some much needed recovery after combat, although stat seals such as Bracing Stance and Atk/Def Bond are also a great choice.

Weapon: Alondite(+Eff)

Assist: Positional Assist

Special: Black Luna

Passive A: Warding Breath / Steady Breath / Atk/Res Unity

Passive B: Slick Fighter / Special Fighter

Passive C: Joint Drive Atk / Preference

Sacred Seal: Mystic Boost / Mirror Stance

• The Black Knight is a great superunit for AR Offense purposes thanks to his inbuilt Distant Counter weapon, which grants him a free A slot instead of being forced to run Distant Counter. 
• Breath skills give the Black Knight +1 Special cooldown during enemy phase, allowing him to have a fully charged Black Luna ready after being attacked. Atk/Res Unity is also a decent option, although it necessitates running Special Fighter to retain increased special cooldown during Enemy Phase, making a Breath skill in conjunction with Slick Fighter a superior option(as the Black Knight can then ward off some Impact users as well as debuffs thanks to the guaranteed follow-up attack it grants and it’s penalty nullification respectively). 
• Joint Drive Atk further boosts the Black Knights Attack as long as he has an ally within 2 spaces, although this can be replaced according to player preference.
• Finally, Mystic Boost and stat boosting sacred seals such as Mirror Stance are the Black Knight’s best sacred seal options, giving him after combat healing and more stats duing enemy phase respectively.