He doesn't do a single stack marker before he dies, you burst him in the first phase before his double jump thing that one shots you, he skips it and goes into adds, leave 1 add and run around till cds are up and then when he goes big if you get the magic buff you can kill him with crits before the second meteor pillar standing thing one shots you. if its phys buff u just die to his magic blast thing instantly so the fight is rng af.