What you talking about lol? First, he is playing broken class/build, second he clearly buys equipment for real money as he showed his gear week of season started and he has 3GA already. Third, midseason patch introduced another game breaking glitch (patched few hours ago), antivein potion boosted HP multiple times insteed by 15%, checked on my sorc and boosted HP from 20k to over 660k.
I mainly plays sorc so my spiritborn is like 25% power of his (Im able to finnish PIT120-125 without elixir glitch) and with elixir glitch I cleared PIT150 solo under 5min at 1st try, later I was running it with random parties and multiple times we achieved less than 2 minutes clears. There's no much about skill to do this, just broken build with right equipment plus broken elixir and some rng luck, you are basically invisible and running from elite pack to another elite pack and "one hitting" them, including boss. Just watch video he posted.