Moon | Caster | Single-target DPS | Impact
Noble Princess Frey is a single-target dps that starts best on Destruction (4pc) + Valor (2pc) with Speed necklace and ATK% ring. From there, move into the Endgame route once the core stat line is stable.
Noble Princess Frey feels best once Speed, Crit Rate, and Crit DMG are online, giving the first rotation a much steadier payoff.
Skill investment is cleanest as Ultimate >= Special >= Basic, with the first cooldown setting the pace for the full rotation.
Lead with the highest-invested cooldown so the opener starts on the strongest possible breakpoint.
Special is usually the next meaningful breakpoint once the opener lands and should carry the mid-cycle payoff.
Use Basic between cooldowns while you keep Speed and Crit Rate stable on gear.
Budget target is 3 / 3 / 3, with 7 / 7 / 8 as the long-term skill finish.
Start on the Budget line with Destruction (4pc) + Valor (2pc) and Speed necklace and ATK% ring. Move into the Endgame route once the baseline is stable.
BudgetBudget
Destruction (4pc) + Valor (2pc) Budget keeps SPD on the necklace and ATK% on the ring.Endgame
Insight (4pc) + Valor (2pc) The source keeps both crit-damage and crit-rate routes alive depending on account quality.Priorities
Target Stats
Lock Speed necklace and ATK% ring, then stack Speed, Crit Rate, Crit DMG, and ATK% through substats.
Upgrade Path
Journey: Hard
Core line: Lacy and Muriel. Fill the remaining slots with Bunny Frey, Charlotte, and Petra or Naru.
Lacy Core 
Muriel Core Bunny Frey Flex 1 
Charlotte Flex 2 
Petra Flex 3 
Naru Flex 3 Skill Cards
Passive
Noble Princess Frey's passive matters more once the core stat line is online and the rotation is already stable.
Basic
Use the basic to bridge cooldowns; it should stay behind the two higher-impact skills in upgrade priority.
Special
Special is the next major breakpoint after the opener and usually carries the mid-cycle payoff.
Ultimate
Ultimate anchors the opener and stays at the top of the investment order for this build.
