In essence, use Ethereal when the big burst turns are going to go off (just watch the debuff countdown), otherwise use Alpha Strike. Take tranquility in the other slot. For the flowing spirit, you can swap the carry pet in and out during the elemental's first 2 turns as they are geyser->whirlpool, o...

I've swapped in a Nexus Whelpling for the Emerald Proto against Hyuna of the Shrines and it feels faster (though I spose prone to occasional RNG). The speed increase is probably worth that chance though. Chi-Chi seems ideal against the water (flowing) spirit rather than other flying pets. The 3rd pe...

This may not be the most readily available strategy to everyone, but I've found that Chi-Chi deals handily with Shu. Evanescence (or whatever that move is called) deals with the Whirlpool and rupture or sandstorm, Tranquility outheals quake. Bring something to finish off mutilator to be sure, but I ...