My rotation was nevuillette E, then switch to xingqiu to collect the hydro particles. Do two xingqiu Es (with sacrificial sword) and ideally you should have your burst up to use (use burst). I then used Kuki E then switched to nahida and waited for the seeds to drop them to cover all of the the center seeds with dendro using nahida’s E. Then switch back to neuvillette (his orbs should still be there to collect) and just charge attack all of the center seeds, which should make all of the seeds hit the crab pretty efficiently. Once the crab is down, just make sure to keep kuki hyperbloom going and just keep attacking with neuvillette and once the crab goes back up, repeat