He Haun Dao - Tianshu (Ability 0)
Autocast: Turn Invisible
Level 1: %Chance (20?) to cleave for 150 x (Sha Yi Stacks) + (Nei Xi + 0.2 x Ling Li) x Weapon Mastery
Level 2: Ti Gu (1st Ability) reduces Armour by Sha Yi Stacks and Magic Resist by the lower of Sha Yi Stacks or 20, also grants Ti Gu a chance to reduce damage output of target by 20 (%?) & gain 3 Sha Yi stacks
Level 3: I think this increases Sha Yi Stacks
Level 4: If Jiao Sha (3rd Ability) hits multiple times, gain -20 (%?) damage taken, +30% damage dealt, 100 attack speed and 10% movespeed for 10 seconds
Level 5: Si Wang Zhan Fang removes the Sha Yi cap and hits +20 times

Ti Gu (Ability 1)
Damage = 300 x Ability Level + (Nei Xi + 0.5 x Ling Li) x Weapon Mastery x 2 x Ability Level
Gain +1 Sha Yi Charge per use

Ruo Dian Da Ji (Ability 2)
Damage = 300 x Ability Level + 2 x Ability Level x (Nei Xi + 0.5 x Ling Li) x Weapon Mastery
Double Damage if behind target
Stuns
On kill: Refresh Skill, +1 Sha Yi Charge, Gain a damage reduction buff that stacks 5 times for 6 seconds

Jiao Sha (Ability 3)
Damage = AbilityLevel x 1000 + 3 x AbilityLevel x (Nei Xi + 0.5 x Ling Li) x (1.5 x Weapon Mastery) x (Sha Yi x 0.2)
(Less damage with less Sha Yi Charges, 100% bonus at 5)
5% + 3.33% chance for every Sha Yi point over 20 to hit twice, 1.67% + 1.11% chance for a 3rd hit.
1st hit Magic, 2nd + 3rd Pure
Consumes all Sha Yi

Si Wang Zhan Fang (Ability 4)
Certain number of hits per cast (no idea what), random target each hit
Damage per hit = (Nei Xi + 0.5 x Ling Li) x Sha Yi (When cast) x Weapon Mastery
Chance to gain +1 Sha Yi every hit
Area damage at end = (Nei Xi + 0.5 x Ling Li) x Sha Yi (At end) x Weapon Mastery / 3
Consumes all Sha Yi

So focus Nei Xi -> Ling Li, Spam Ti Gu to max charges then burst with Jiao Sha or Si Wang Zhan Fang. She's definitely just a single target machine, but contributes nothing in the early game really.