Lei Shi is a single-phase fight and when she reaches 80%, 60%, 40%, and 20% health, she summons 3 water elementals, and goes immune until at least one add has been killed. She has two special abilities causing her to either disappear until damaged by AoE attacks or she will channel wind spell that pushes players away from her and damages them until she has been damaged 4% of her health.
Instead, of performing melee attacks, Lei Shi constantly casts Spray at her current target which deals a large amount of Frost damage to them and anyone within 2.5 yards of them. Getting hit by Spray also adds a stacking debuff which increases Frost damage taken by 16% per stack, for 10 seconds.
Every 10% Lei Shi will gain a stack of Afraid which will increase her casting speed 8% per stack which results in Spray being cast more frequently.
If you have fought Lei Shi on Raid Finder mode the fight is almost identical and therefore the strategy is the same. To minimise damage t the tanks they should alternate to avoid the Spray debuff getting too high;
- During Hide, players should spread out and do AoE attacks to find Lei Shi;
- During Get Away!, run towards her and use attacks that can be dealt while moving;
- During Protect, focus down one of the water elementals while the rest are crowd controlled or tanked (when the one is killed the rest vaanish
Optimal positioning to minimise raid damage is to form a triangle centred around Lei Shi with tanks at 2 corners and the raid at the 3rd corner. This allows the tanks to taunt Lei Shi without having them both affected affected by the same Spray, while the raid can remain spray free.
There are 3 main sources of damage are Spray, the water elementals and Get Away!
Tank switching deals with Spray as best as possible and crowd controlling the water elementals (Banish, Bind Elemental, Freezing Trap) you are not killing as this removes the need to tank them as they deal very high melee damage.
Get Away! is handled by simply running to Lei Shi as this halves the damage at the cost of reduced DPS unless you are able to use class abilities like Spiritwalker's Grace or Kil'jaeden's Cunning. As Get Away! only ends after Lei Shi loses 4% of her health it is a good time to use personal defensive cooldowns, instant AoE heals. If you can't heal and have instant offensive attacks you can use against Lei Shi you should do so.