TakinaLimited

When Takina first released, many felt she was more lukewarm than expected, but over time her rating rose as a Nikke with clear use in hard stages.
Her role is clear: from the B2 slot she applies damage taken increase to enemies and DEF-ignore damage increase to allies, boosting the whole team's damage. Many suggest getting at least one copy if she is a limited character.

Combat Support1 adds ATK and DEF-ignore buffs to herself at battle start and at each Full Burst end and start, building her base damage.

Battlefield Control2 applies all-enemy damage taken increase and stun along with all-ally DEF-ignore damage increase at the same time, creating windows where the whole team can focus damage.

Her Burst Suppression InitiatedB changes her weapon for 10 seconds, turns normal attacks into DEF-ignoring damage, and applies extra damage taken increase to targets hit. In short, Takina boosts her own damage and supports ally damage together during Burst.

Auto is enough for basic use.
However, timing her Burst manually only when you want to line it up precisely with boss patterns or burst damage windows improves efficiency.

Takina provides enemy damage taken increase and ally DEF-ignore damage increase at the same time from B2, so pairing her with DPS who dump damage in short windows works well.

For Sniper Rifle stability first, prioritize Resilience Cube. Bastion Cube is next, and adjust with Onslaught Cube for a more offensive lean.

Set Iron Elemental Advantage damage and ATK first, and use remaining lines on Max Ammo for stability. Adjust Charge Damage and crit lines lower in priority depending on gear.

S2 is the core, so bring it to 10 first, and raise Burst while watching its actual damage contribution. Investing in S1 last causes no big problems.

Good in story, bosses, and Tower as B2 support and damage assist. Her priority is fairly low in Arena.

She provides both enemy damage taken increase and ally DEF-ignore damage increase, making it easy to raise team damage.

As a Sniper Rifle, her real performance varies with accuracy and Charge handling.

Takina shows her value best when fielded not as a solo carry but in the B2 role pushing the whole team's damage.