Prune is a support that relies on triggering the Swirl reaction to buff characters. Triggering Swirl will convert her Banehunter Oathhammer (Skill) into the element she Swirls, and as long as her A4 talent is unlocked, hitting opponents with a converted Banehunter Oathhammer or her Burst will activate the Tolling Rally effect, which will provide DMG buffs to the team based on Prune's ATK. In addition, when a Hexerei character under Tolling Rally triggers a reaction, Prune gains an ATK% boost, and if that reaction was Swirl, the triggering character also gains an ATK% boost.
Prune's [C1] let's her restore 2 Energy every 1.8 seconds whenever a converted Banehunter Oathhammer hits opponents. How much total energy she can restore depends how often Prune is able to trigger Swirl during the duration of her Burst. Prune's [C6] increases her Burst duration by 4 seconds.
Tolling Rally does not apply to Prune herself.
Tolling Rally caps out at 4,000 ATK, usually not feasible to get unless Prune is in a Hexerei team.
Talent levels are not a necessity as they do not increase Prune's buffing capabilities.
Regarding Weapon Choices:
Favonius Codex: In teams where Energy isn't much of an issue for Prune or the team, it is better to use a weapon that provides more ATK.
Thrilling Tales of Dragon Slayers: While this weapon significantly decreases the value of Prune's buff due to its low Base Attack, it can provide a 48% ATK boost to the DPS, which can be valuable depending on the team she is in.
Regarding Artifact Choices:
Sets
Viridescent Venerer (4): Interchangeable with (4) depending on if there are members in the team that are already holding one or the other set.
Celestial Gift (4): Interchangeable with (4) depending on if there are members in the team that are already holding one or the other set.
Main Stats
CRIT Rate: Only recommended if using a Favonius weapon.
Substats
Energy Recharge: Prioritize until requirements are met.
CRIT Rate: Only recommended if using a Favonius weapon.