Flins functions as a premier Lunar-Charged Main DPS, built around triggering and amplifying the Lunar-Charged reaction essentially a stronger, CRIT-capable version of Electro-Charged — through his Elemental Skill and Burst combo. A unique passive also converts a portion of his ATK into Elemental Mastery, meaning building ATK directly feeds into his reaction damage.

For artifacts, Night of the Sky's Unveiling is his clear best-in-slot, and its 4-piece bonus can reduce his CRIT Rate requirements by up to 30%, freeing you to focus heavily on other stats.

Because of this, aim for around 40–50% CRIT Rate before the artifact bonus kicks in, and push CRIT DMG to 175% or above. On top of that, Energy Recharge is critical for Flins — target 130–140% when running double Electro, as his Special Burst is a core part of his damage and needs to be reliably available each rotation.

For ATK, 2,500 or more is the practical goal, as hitting 2,000 ATK also caps out his Elemental Mastery conversion passive at 160 bonus EM, further boosting his reaction damage. Note that Flins prefers an ATK% Goblet over Electro DMG Bonus, since the majority of his damage comes from Lunar-Charged rather than raw Electro hits.