Diesel: Winter Sweets

YES. If she enters Full Burst without using her own Burst Skill (the Highlight path), Skill 1 grants Sustained Damage +235.03% for 10s — extremely strong in a fast-burst squad. Skill 2 stacks a buff when allies break enemy parts, and a Full Charge shot adds +318.14% Sustained Damage for 3s. Her Burst, La La La, deals continuous Sustained Damage to all enemies plus an extra 181.2% to the stage target, while also raising enemy damage taken by 25.09%. A strong sustained-AoE Attacker — worth pulling for squads that need reliable finishing damage.

Diesel: Winter Sweets is a Fire Attacker, burst III, using an RL — her burst damage scales heavily on how she enters Full Burst.

• On Full Burst entry she gains +20.28% Crit Damage permanently; entering via her own Burst Skill (Intro) adds +60.19% Sustained Damage for 10s, while entering without using Burst (Highlight) grants a massive +235.03% Sustained Damage for 10s.
• Full Charge attacks grant +318.14% Sustained Damage for 3s, and destroying enemy parts adds another +68.04% Sustained Damage for 15s.
• Her burst La La La inflicts +25.09% Damage Taken plus 18.43% ATK sustained damage per second for 9s (the stage target takes +181.2%/sec), on a 40s cooldown.

Her ceiling is huge if you can time Full Burst entry via Highlight rather than her own Burst, but the mechanic is fiddly — comps that can't set up that specific entry lose most of her potential.

Prioritize S2 first — it opens multiple sustained damage sources: on part destruction, on Full Charge hits, and on Full Burst entry. Next Burst since it raises AoE Damage Taken plus heavy sustained damage on the stage target. S1 last since it only boosts Critical Damage and sustained damage buff on Full Burst entry, conditional on entry method.

4/4/4 (playable) → 7/4/7 → 10/4/10 (final, as a sustained-AoE Attacker). Prioritize Burst (AoE DoT + enemy damage-taken debuff) and Skill 1 (Sustained Damage +235.03% on Highlight entry) first; Skill 2 (part-break buff) can wait.

Strengths

• High SSR base stats (HP 583734 · ATK 25554), among the strongest Attackers in the current data.
• A full role change from Defender to Attacker, adding a new main-damage option for a squad that otherwise lacks a pure Attacker.
• Uses an AoE Rocket Launcher, pairing well with base Diesel's taunt for a safe damage-dealing setup.

Weaknesses

• Both element (Iron→Fire) and role changed compared to base Diesel, so her kit can't be inferred from the original.
• Like all RL users in the data, she needs a 1-second charge for full damage, easy to disrupt under constant interruption.