First up, the Blighthawk. Rockbiter starts with Nature's Ward, but the Blighthawk is faster so you can get a Ghostly Bite in before he swaps to elemental. After the bite, swap to the Jademist Dancer. Get Acid Rain up, even though he's underground this will amp your damage. When he pops back up, reload your life with Rain Dance. It will also make the next 2 attacks greater critical chance. From here, you get 2 rounds of critical Steam Vent. It should take him out or close to it. When he goes down, you can ride the Jademist dancer out as long as you can, or swap into the Blighthawk. If you time it right, you can get a round of increased critical chance for the Blighthawk's Ghostly Bite. Either way, there's plenty of tools to use with the Blighthawk. You can use Lift-Off to avoid damage, or just spam Infected Claw. When he's down, swap into the Stitched Pup. All that's left is to Howl and spam Diseased Bite up. Once you have Howl up, you can always flip to the Blighthawk for another crazy Ghostly Bite!