MiyabiPick #2 of 5 · S1
A solid alternative: it adds combat ATK and a PEN Ratio secondary stat. It has no CRIT, so you need more CRIT Rate from discs; at S3–S5 it gets fairly close to S1 Hailstorm Shrine.
Effect
Data Flood
Increases ATK by 12%.
When using a Special Attack or EX Special Attack, the equipper’s Anomaly Proficiency is increased by 25 for 8s, stacking up to 3 times.
The duration of each stack is calculated separately.
*Stats shown are at Base level.
Values at S1/S2/S3/S4/S5
Who Should Use Fusion Compiler
Ranks and notes come from each Agent's build guide on Zenless Builds.
AlicePick #3 of 5 · S1
An accessible pick with 24% PEN Ratio and combat ATK. Its stacking Anomaly Proficiency needs frequent Special/EX Special Attacks. If you can't keep the stacks up, it drops off noticeably and may fall behind the A-Rank options below. It gets much stronger with refinements.
GracePick #3 of 6 · S1
Her signature, permanently available and the most used: unconditional ATK and PEN Ratio plus stacking Anomaly Proficiency on Special Attacks, a great fit for her EX-focused kit. Only about 2% behind the two above.
JanePick #3 of 6 · S1
Fairly strong since its PEN Ratio main stat isn't saturated by team buffs the way ATK is. Its short stacks are tricky to keep, requiring frequent regular Special Attacks because there isn't enough Energy for EX Special Attacks alone; it improves with dupes.
PromeiaPick #3 of 5 · S1
At S5 it is almost as strong as her signature; at S1 it is still the best budget option. The extra ATK and the Anomaly Proficiency stacks from her Specials are almost always maxed. Its PEN Ratio clashes a little with her DEF ignore, and the lack of Anomaly Mastery can change your routing; with this W-Engine, a PEN Ratio Disc 5 plus 2-piece Puffer Electro can give the highest personal damage.
Remielle DanPick #4 of 5 · S1
Gives 12% ATK and stacking Anomaly Proficiency on Special/EX Special Attacks; a usable stopgap if you already own it.
VivianPick #4 of 5 · S1
PEN Ratio, ATK and stacking Anomaly Proficiency from Special/EX Special Attacks; only worth it if you lack the options above.
YanagiPick #4 of 5 · S1
Its PEN Ratio secondary stat suits Yanagi well, and it adds combat ATK plus stacking Anomaly Proficiency on Special Attacks. At S3 or higher it gets close to her signature. With this W-Engine or alongside Rina, a PEN Ratio Disc 5 is preferred over Electric DMG.
AriaPick #5 of 5 · S1
Usable since Aria often casts Full-Sugar Electronica - No Ice and her cheap EX Special. The catch is that each stack lasts only 8s, so it's hard to maintain and you'll need dedicated routing.
Velina AirgidPick #5 of 6 · S1
An Anomaly W-Engine option: 12% ATK and stacking Anomaly Proficiency on EX Special Attacks, but no Energy Regen for her Core Passive.
PiperPick #6 of 6 · S1
An alternative: PEN Ratio, ATK and Anomaly Proficiency stacks whenever she uses Special Attacks, which suits Piper's constant spinning.