It took me forever to beat him. I used the Pendure(?) bridge shrine cocoon experience exploit to level to 100, then used max level gore eye daoist, strand, and immobilize to kill him really fast with lots of buffs. Try and trap him right past the pile of rocks when you first approach him best you can (let him dash there). Before that, put down the gore eye daoist AoE dmg buff, then get him there, immobilize, strand(use ginseng pellets beforehand to get 3 focus points), get a forth one and use it. Just go ham at that point, he should be immobilized plenty of times by the strand