Diabolist — guide

In short

Diabolist is a Rare Support champion of the Demons faction with Magic affinity. Her job is the Increase SPD 30% buff for the whole team plus turn-meter manipulation — she speeds allies up and slows enemies down. Build priority is Speed and survivability, not damage.

Strengths

• Thunder and Lightning (A2): hits all enemies and applies Increase SPD 30% for 2 turns to all allies — a universally useful buff.
• Charge (A3): fills allies' turn meters by 15% and reduces enemies' by 15%. No ACC check, so it needs no Accuracy investment.
• A2 damage scales off DEF, so building her tanky doesn't waste the skill entirely.
• Faction Wars rating 3.5 — her best area by far for a Rare.
• Rare rarity means cheap books and easy early investment.

Weaknesses

• Torment (A1) has only a 10% chance to place Sleep — it almost never lands.
• Low base stats: 1,002 ATK and 782 DEF, so she brings no real damage.
• Despite being Support, she has no heal and no debuff cleanse.
• Ratings of 2.0 in Clan Boss, Hydra, Chimera, Hard mode and Doom Tower — not endgame material.

Where to use

Start with Faction Wars (3.5) — Demons want Speed and A3 helps clear waves. Next is Arena (3.0), but only early: the SPD buff and turn-meter cut give a cheap team the first turn. Dungeons (3.0) is also a starter use. Skip her in Clan Boss, Hydra, Chimera, Hard mode and Doom Tower (all 2.0).

Stats and gear

• Speed first: roughly 170–200 for Faction Wars and dungeons, 200+ for Arena — Speed boots are mandatory.
• HP% gloves and chest, DEF/HP amulet — she has to survive until her second A3.
• Accuracy is nearly pointless: the only debuff is a 10% Sleep on A1. 50–100 is plenty if you have nothing better to roll.
• Ignore C.RATE and C.DMG entirely.
• Sets: Speed and Health, exactly as recommended for her; from the relic list, Journal of Necrotos.

Masteries and blessings

The Support tree is her home: take Invigorated from the build list and fill the rest toward speed and survivability. Second tree is Defense so she lives long enough for A2/A3 to come back up. Blessings: any defensive option — for a Rare this is not a priority.

Tombs

Book Charge (A3) first — it has two −1 cooldown levels and this is the skill that makes her worth a slot. Then Thunder and Lightning (A2) for the −1 cooldown at level 4, so the SPD buff stays up more often. Leave A1 alone; +5% Sleep chance changes nothing.

Verdict

A cheap early Support for Arena and Faction Wars, then vault material (fusion). She has no place in endgame content.