Nyna

Weapon: Respite+ / Grandscratcher+ / Palm Staff+ / Staff of Twelve+ / flexible

Assist: Rescue+ / Restore+ / Flexible

Special: Imbue / Flexible

IVs: +HP or +Atk or +Res / -Def

Passive A: Fortress Res / HP +5 / Flexible

Passive B: Sabotage Atk / Any Sabotage / Chill Def/Res 3 / Flexible

Passive C: Infantry Pulse / Infantry Breath / Odd Recovery / Even Recovery / flexible

Sacred Seal: Distant Guard / Any Spur or Drive / HP+5 / Phantom Res / flexible

• Nyna has no unique skills to offer, and generic staff units do not have great combat at this point. However, they do have access to some useful support skills like Respite+ and Grandscratcher+. Respite essentially acts as Drive Guard plus a minor stat boost of Def and Res +2, causing allies within two spaces of Nyna to slow their foe’s Special charge. This can be a valuable effect for supporting an enemy phase unit that does not have a Guard effect in their own kit. Grandscratcher provides 1 Special charge at the start of turn 1 to Nyna’s ally with the highest visible Atk, which can be more than one unit if their visible Atk stats are equal. This is a great effect if your team needs to charge up a Special like Blazing Wind or Lethality before entering combat, as long as the relevant unit has enough visible Atk. Palm Staff+ can also be a good choice if Nyna is used in a Save ball where she can debuff the Atk and Spd of nearby enemies while her Saviors are in combat with them. Staff of Twelve+ is also a decent support effect that provides some start-of-turn healing to allies. 
• The other skills are highly flexible and depend on the needs of the team, and in some cases the other skills chosen. 
• If Nyna is used as a support unit for a tank, skills that improve their bulk or combat like Infantry Breath or Distant Guard are useful. If she’s used to support infantry units that need to charge Specials on turn 1, then Infantry Pulse can provide another charge on top of Grandscratcher. HP-boosting skills are good to pair with this, since Nyna needs to have higher HP than infantry allies to Pulse them. A Sabotage B skill like Sabotage Atk is also a good support option for tanks, which pairs well with effects that boost Res for comparisons like Fortress Res and Phantom Res. 
• The Assist is flexible. Restore+ is a good option to heal an ally and remove any debuffs they have. Movement healing options like Rescue+ and Return+ can be good for providing healing as well as being able to pull allies out of enemy range. Other pure heals like Physic+ can also be useful if Nyna needs to stay a space away. 
• The boon is flexible. +HP is useful for the Infantry Pulse HP check, while +Res is useful for Sabotage. +Atk is a good neutral option that slightly improves the amount of HP Nyna heals with her Assist skill. -Def is generally a fine bane, since Nyna’s Def is already bad and lowering it further doesn’t impact her performance much. 
• In addition to previously mentioned C skills, Odd Recovery and Even Recovery provide some start-of-turn healing to nearby allies, as well as removing debuffs, at the start of odd and even numbered turns respectively. 
• The Special is highly flexible, with Imbue+ being a low-cooldown option that provides some extra healing on every other heal. Stat-boosting options like Windfire Balm+ can be situationally good.