Guide
How the kit works
Before a fight, use Splitting Spearhead to gain 40% ATK at the start of the next battle for 3 turns. In battle, Cloudlancer Art: Torrent deals Wind DMG equal to 260% of ATK to one enemy at the listed level. A CRIT Hit gives it a 100% base chance to reduce that target's SPD by 12% for 2 turns.
Use Ethereal Dream against a Slowed target when you can. Its listed multiplier is 400% of ATK, rising by 120% if the enemy is Slowed. Superiority of Reach gives Dan Heng's next attack 36% Wind RES PEN when an ally targets him with an ability. It can trigger again after 2 turns, so try to have that next attack hit a worthwhile target.
Cloudlancer Art: North Wind deals Wind DMG equal to 100% of ATK to one enemy. High Gale makes the Basic deal 40% more damage to Slowed enemies. Faster Than Light has a 50% fixed chance to increase Dan Heng's SPD by 20% for 2 turns after he attacks. Hidden Dragon reduces his chance of being attacked when his HP is at or below 50%.
Build and why
For relics, start with 4 pieces of Pioneer Diver of Dead Waters. Its 2-piece effect increases damage against enemies with debuffs by 12%. The 4-piece effect gives CRIT Rate and more CRIT DMG against enemies with at least 2 or 3 debuffs; its effects increase after the wearer inflicts a debuff. Dan Heng's Slow helps with that setup.
Scholar Lost in Erudition is another option: it gives CRIT Rate and increases Skill and Ultimate damage. After an Ultimate, it also increases the next Skill's damage. Eagle of Twilight Line gives Wind DMG and advances Dan Heng's action by 25% after his Ultimate. For planar ornaments, Rutilant Arena gives CRIT Rate and boosts Basic and Skill damage at 70% current CRIT Rate. Firmament Frontline: Glamoth gives ATK and damage at its SPD thresholds.
Use CRIT Rate or CRIT DMG on the body, SPD or ATK Percentage on the feet, Wind DMG Boost on the sphere and ATK Percentage on the rope. For substats, follow CRIT Rate, CRIT DMG, ATK Percentage, then SPD. CRIT Rate helps the Skill trigger its Slow condition.
In the Night is the first Light Cone choice. It gives CRIT Rate, and SPD above 100 increases Basic and Skill damage as well as Ultimate CRIT DMG. Swordplay rewards repeated hits on the same target, but loses its stacks when you change targets. Sleep Like the Dead gives CRIT DMG and can grant CRIT Rate after a Basic or Skill fails to land a CRIT Hit. Cruising in the Stellar Sea is another option with CRIT Rate and an ATK increase after a defeat.
Leveling priority
Follow the game's order: level Cloudlancer Art: Torrent first, then Ethereal Dream, Superiority of Reach and Cloudlancer Art: North Wind. The Skill is your way to apply Slow, while the Ultimate benefits from attacking a Slowed enemy. The Talent improves the Wind RES PEN of the next attack after an ally targets Dan Heng.
For maximum ascension, gather 246,400 Credit, 50 Storm Eye, 12 Extinguished Core, 13 Glimmering Core and 12 Squirming Core. To level all skills to their maximum, you need 2,400,000 Credit, 5 Tracks of Destiny, 12 Arrow of the Beast Hunter, 54 Arrow of the Demon Slayer, 105 Arrow of the Starchaser, 12 Destroyer's Final Road, 28 Extinguished Core, 42 Glimmering Core and 42 Squirming Core.
Eidolons worth it
For eidolons, I would consider Quell the Venom Octet, Quench the Vice O'Flame first. It reduces the Talent cooldown by 1 turn, letting you activate its Wind RES PEN effect more often when an ally targets Dan Heng.
Roaring Dragon and Soaring Sun is another option: if the Ultimate defeats an enemy, Dan Heng acts again immediately. The Higher You Fly, the Harder You Fall gives 12% CRIT Rate while the target has at least 50% HP, which helps with the Skill's CRIT Hit condition.
The Troubled Soul Lies in Wait is worth considering if you want a stronger Slow: it reduces the target's SPD by an extra 8%. Seen and Unseen and A Drop of Rain Feeds a Torrent raise skill levels rather than adding a new mechanic. You can stop at E2 if that is enough for your build; the later eidolons are optional.
Teams
Dan Heng wants teammates who can support his single-target damage and keep the team alive. Have an ally use an ability targeting him to activate Superiority of Reach, then use the improved next attack on the enemy you want to focus.
Fu Xuan is a Quantum sustain option. Sparkle is a Quantum buffer, while Bronya is a Wind buffer. Huohuo is another sustain option and shares Dan Heng's Wind element. Choose the support roles your team needs rather than treating a particular element as a requirement.
Welt is an Imaginary debuffer, and Silver Wolf is a Quantum debuffer. Debuffs from a teammate can help Dan Heng use the effects of Pioneer Diver of Dead Waters against enemies with multiple debuffs. His own contribution is focused Wind damage and a Slow from his Skill.
Common mistakes
Don't fire Ethereal Dream without checking the target's Slow if you can apply it first. Cloudlancer Art: Torrent needs a CRIT Hit for its Slow attempt, and the listed 100% is a base chance, not a promise that every Skill will Slow.
Don't overlook Superiority of Reach. An ally has to target Dan Heng with an ability, and the Wind RES PEN applies to his next attack. Watch the cooldown before planning around another activation.
Don't assume Rutilant Arena is boosting damage below 70% current CRIT Rate, or that Firmament Frontline: Glamoth has reached its damage thresholds without checking SPD. Faster Than Light can raise SPD after an attack, but its activation has a 50% fixed chance. If you use Swordplay, changing targets removes its stacks.
