Biscuit

An Electric Code Burst 2 Supporter used in the Arena for Defender invincibility and cover repair.
Since the summer patch, invincibility has lost value in the spread and shared damage meta, and she is rarely a main pick in PvE or Raids.

Each time Full Burst ends, Happy Puppy1 grants all Attacker allies normal attack Increased Critical Rate and continuous healing based on Max HP. When a Defender ally drops to 50% HP or below, Tug of War2 triggers 5 seconds of invincibility and healing (2 times per battle). Walk TrainingB repairs the cover of 2 allies whose cover was destroyed and grants all Supporter allies Increased ATK and healing based on attack damage.

Tug of War2 does not trigger if a single hit removes 50% or more of HP, and a Defender who already used invincibility must recover above 50% HP and get hit again to retrigger it. Her Burst cooldown is 40 seconds.

Set Burst order so the Happy Puppy1 buff lands each time Full Burst ends.
Tug of War2 invincibility triggers only when a Defender drops to 50% or below, so do not count on it against one-shots.
When it is time to repair broken cover with Walk TrainingB, Burst manually.

She may compete for slots with other Defenders and Burst 2 units like Makima and Sin. In PvE, a 1-1-3 damage lineup is usually faster.

For healing and survival support, prioritize Healing Cube and Vigor Cube. In the Arena, tune Burst Gauge with Quantum Cube.

As a buffer, skip ATK and Elemental Advantage damage lines. For Arena, Charge Speed and Max Ammo lines are an option, but low priority.

Survival and buffs feel sufficient at 4 for S1, S2, and Burst. To boost cover repair and Supporter buffs further, raise only Walk TrainingB to 7.

Used in the Arena for defense and sniper counters, and against bosses where cover matters, such as Alteisen (the train) Interception. Rarely a main pick for heavily CP-deficient Story or wave content.

Walk TrainingB repairs broken cover.
Tug of War2 gives Defenders brief invincibility and healing.
Happy Puppy1 heals and buffs Attacker allies every Full Burst.

Tug of War2 does not trigger against one-shots or single hits of 50% or more.
Her Burst cooldown is 40 seconds, so you need another Burst 2 slot.
In a meta of spread and shared damage, invincibility is worth less than before.