I suggest Crimson Archon Shards with ability strength. This boosts the damage on 4 and the nuking. I know there's one for secondary critical chance, but [Titania] just has a low base critical chance on her [Dex Pixia]. From my testing, the damage went up by 59,6% when swapping 5 Crimson Archon Shards with secondary critical chance, to 5 Crimson Archon Shards with ability strength (this was on the Null Star build, so ability strength was low, but I will assume it would still be better on the main build.)

1. Pickup energy orb for [Energy Conversion]
2. Hit enemies with [Grimoire] alt fire
3. Use operator sling chain to gain ability strength
4. Hit with a status proc for Growing Power
5. Press 4
6. Kill everything that moves
7. Profit

ABILITIES:
Roar/Eclipse Helminth for more damage, could also use Fire Walker for speed (can be activated and used in ult)

MODS:
You could swap [Archon Vitality] for [Umbral Vitality], but I think [Archon Vitality] is more beneficial if you build heat on your [Dex Pixia Prime] (which I do on my build linked below). If your not using heat, you should 100% just go with the Umbral Version of the mod.

175% ability efficiency leads to a 1,25 energy/second drain, (wrong number on this site, look ingame) which is the lowest obtainable on [Titania]'s ult.

EXALTED:
[Dex Pixia Prime] Build: Fairy Guns

WEAPONS:
Grimoire Buffer to buff ability strength before casting 4

ARCANES:
Arcane Precision on secondary for pistol damage in ult.

COMPANION:
MOA companion with [Calculated Redirection] + [Reinforced Bond] for 60% fire rate, also [Tenacious Bond] for 1,2x critical multiplier if you use [Vulklok] weapon with a critical chance mod. The parts are: Drex Core, [Lambeo Moa], Hona Bracket, Harpen Gyro
Reinforced Bond Enabler

FOCUS SCHOOL:
Madurai for Sling Strength

Nuke alternative:
Forma Umbral forma on Umbral Intensify and Naramon forma on Streamline.
Thermal Sunder/Null Star + Augment: (I know that Thermal Sunder/Null Star might be meta and the best option, it would, however, require more range than 100% to be worthwhile, I could change the build. But I personally prefer shooting stuff lol. Also also its only viable for low level missions, like fissure runs. But if you want to run it with this forma, do (requires umbral forma however):

Ability 3 -> Null Star (Null Star also destroys creates)
Growing Power -> Corrosive projection
Energy Conversion -> Neutron Star
Fleeting Expertise -> Stretch
Transient Fortitude -> Overextended
Arcane Precision -> Arcane Energize
Arcane Velocity -> Molt Augmented

Ability 3 -> Thermal Sunder
Growing Power -> Corrosive projection
Energy Conversion -> Stretch
Transient Fortitude -> Overextended
Arcane Precision -> Arcane Energize
Arcane Velocity -> Molt Augmented

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