Did this with : any Aquatic Slithershock Elver ( 2-1-1 ) H/P or H/B breed Moonshell Crab ( 1-1-2 )
1- pass, your pet will die bring in your Slithershock Elver 2- Grasp 3- Dive 4- Dodge 5- Grasp until Slithershock Elver die from boss Cannon ability bring in your Moonshell Crab 7- Moon Tears 8- Shell Shield 9- Arcane Slash until fight ends.
I used Emperor crab as above. I then used Moonshell crab as the second pet, using Shell Shield, Moon Tears, 3 x Arcane Slash, Shell Shield, Arcane Slash. I then used Gahz'rooki as the third pet, using Geyser, Tail Slap until below 25%, then Swallow You Whole.