This is your first AoE encounter in the Tomb of Sargeras. In normal and heroic modes though, the AoE part is very small: it is mostly focused on a few high priority targets to kill quickly before going back to the boss, therefore going for single target focused talents (Serenity) is still probably the best thing to do.
You’ll want to move out of the raid to place Aqueous Burst, as they’ll otherwise be quickly annoying to deal with as they stack up.
Stack up with the rest of the group for the most part, to soak the tank hit ( Unchecked Rage).
You’ll want to dodge most abilities to avoid having too many stacks of Drenched , as these will stick around untill the boss casts Draw In. For the most part, avoid taking any unnecessary damage, move away if fixated by murlocs, this is mostly about priority targets and surviving as a group little about dps.
Mythic has a very interesting mechanic for windwalkers: eggs will spawn that take 99% reduced damage, have significant health pools and hatch after around 20 secons. You will need to face the boss on top of them and stack for Unchecked Rage as this ability will remove the damage reduction fully and you’ll then have a few seconds to annihilate the eggs. This allows you, as a windwalker, to tag the eggs before they become a target for more marks of the crane, then to destroy them once they are vulnerable.
Focus on lose tadpole murlocs as they are away from the boss and this fight will feel like heroic. Fail to do so and the boss will enrage quickly and decimate your group.
It is worth noting that on a boss like this one the recent changes to windwalker balance take their full meaning. Fists of Fury is way less relevant to your single target, but with it’s improved range it is a very important AoE spell. If you’re not running with any tier t20, you’ll be willing to delay using fists of fury a LOT to line it up with extra targets. By a lot, I mean that for instance if you’re running serenity, you don’t want to clip Fists of Fury at the end of your first serenity as adds will spawn 5 seconds later and you’ll want to kill them, and nothing trumps a 10 stacks of transfer the power fist to do that job.
Obviously tier 20 comes in to wreck your dreams, as you’ll now want to use it just the Pressure Point. Thankfully, this comes with a highly reduced cooldown so if done right you’re likely able to get the best of both worlds here!
Take any opportunity with no AoE and no boss mechanic to dump stacks of the emperor’s capacitor, even if you only have 15: you’ll find opportunity during the encounter are more valuable than opportunity within your rotation.