Charlotte

Weapon: Fair-Fury Axe

Assist: flexible

Special: Galeforce / Glimmer / flexible

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

Passive A: Swift Sparrow 3 / Atk/Spd Boosting A Slot

Passive B: Frenzy / Null Follow-Up / Wings of Mercy / flexible

Passive C: Time’s Pulse / Odd Tempest / flexible

Sacred Seal:  Blade Session / Brash Assault / flexible

• Charlotte’s amazing offensive statline makes her a great candidate for a player-phase build, Galeforce or otherwise. 
• Fair-Fury Axe is an incredible weapon for this kind of build, reducing Special cooldown and providing a boost of 6 Atk and Spd and true damage equal to 15% of Charlotte’s Atk so long as she either initiates combat or is within 2 spaces of an ally. 
• The Special is chosen based on what role Charlotte plays. Galeforce is great when used on a dedicated team, allowing her to act again after it activates. A damaging Special like Glimmer can be used instead if the extra action is not needed or extra power is desired. A 2-cooldown Special like Glimmer, Moonbow, or Ruptured Sky is ideal because Time’s Pulse charges it fully at the beginning of her turn, allowing her to activate it immediately in her first combat. 
• The ideal choice of boon is either +Atk or +Spd, with both being solid options, Atk increasing her damage and Spd allowing her to gain more damage reduction from Frenzy and win more Spd checks. Any of the other three stats is a good choice for bane, with -Res being arguably the best, since Charlotte’s Res is already terrible and most enemies that can counter in melee hit Def, apart from dragons and a few rare others. 
• The ideal choice of A skill is one that boosts Atk and Spd on player phase, with her native Swift Sparrow 3 being a great option. 
• The B skill is flexible. Frenzy is a solid option that reduces Charlotte’s damage taken by up to 40% depending on the difference between her Spd and her foe’s, while also allowing her to follow-up before her foe counters if she is below 50% HP. However, it does nothing to guarantee a follow-up or prevent follow-ups being blocked by skills such as Wary Fighter. Because of this, Null Follow-Up can also be a solid option that allows Charlotte to break through those skills and prevent foes from guaranteeing follow-ups against her. Wings of Mercy has use on Galeforce teams, if Charlotte needs to teleport next to another unit that is below 50% HP. It is generally not the best option outside of that context. 
• The C skill is also flexible. Time’s Pulse is a great option for all builds that charges Charlotte’s Special by 1 at the start of her turn, if it is at its maximum cooldown. For a 2-cooldown Special like Glimmer, with its cooldown reduced by 1 by Fair-Fury Axe, this means she charges it fully and can immediately activate it in her first combat. For Galeforce, it will not be charged fully without significant help from other units using skills like Infantry Pulse, but the extra charge is still helpful. Other skills such as Odd Tempest or Even Tempest can also be useful to give Charlotte more mov on certain turns. 
• The seal is flexible, with Blade Session being a great option that boosts Charlotte’s Atk and Spd by either 3, 6, or 9 on player phase depending on whether 0, 1, or 2 or more allies are alive and have ended their turn before she acts. 9 Atk and Spd is the largest boost available from a Seal at time of writing. Brash Assault is also an interesting option that pairs well with Frenzy, allowing Charlotte to gain a guaranteed follow-up attack when she is at 50% HP or less, and also make that attack before the foe can counterattack because of Frenzy. 

Weapon: Fair-Fury Axe

Assist: flexible

Special: Glimmer / Noontime / flexible

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

Passive A: Distant Counter / flexible

Passive B: Spurn / Frenzy / flexible

Passive C: Joint Drive Spd / Pulse Smoke / flexible

Sacred Seal: Mystic Boost / Atk/Spd Solo / flexible

• While Charlotte’s defensive stats are low, her great Atk, Spd, HP, and ability to use Spd-based damage reduction B skills allow her to function well as a tank. 
• The choice of Special is flexible. A 2-cooldown Special like Glimmer or Noontime is ideal if Charlotte is not receiving support from a unit that grants Special cooldown such as Summer Hilda, Glimmer for extra damage or Noontime for healing. If she is receiving such support, a 3-cooldown Special like Luna or Sol can be used instead. 
• The ideal A skill is Distant Counter if Charlotte is being used to tank all types of enemies, as it allows her to counterattack ranged foes. If she is primarily used against melee foes, such as when paired with an ally using A/R Far Save, then another A skill can be used instead to boost her stats, such as Atk/Spd Solo. 
• The ideal B skill is Spurn, as Frenzy’s secondary effect of Desperation 2 is only active on player phase, and this build is primarily designed to function on enemy phase. The extra 5 damage on Special activation from Spurn is consistently useful, making it the best choice for Spd-based damage reduction in most modes. However, the difference in performance is not large, and Frenzy is an acceptable substitute. 
• The C skill is flexible, with Joint Drive Spd being a good choice to increase Charlotte’s Spd by 4 so long as she has an ally within 2 spaces, and Pulse Smoke another good choice that increases the Special cooldown of her foe and any foes within 2 spaces of them by 1 after combat. 
• The seal is also flexible, with Mystic Boost providing two useful effects in after-combat healing and disabling Wrathful Staff and similar effects. A stat-boosting seal like Atk/Spd Solo is also a good option.