For the first phase, start with a slash to bait a charge, then use the whirlwind and do 6 basic attacks, walk away from him, re-use whirlwind and re-do 6 basic attacks.
For the second phase, slash the blastworms, whirlwind one into him when he goes down, then do 4 basic attacks then a spin attack, repeat another time.

Note 1: for second phase, you can do 4 basic attacks then a spin attack or 6 basic attacks.
Note 2: if a blastworms explods and touch Stagnox, then it will deal additionnal damages, but he will wake up earlier and break the pattern.

Last updated 05/14/2018 – Stovent