I generally do not like the Uber Lilith challenge as she can be the most difficult boss in the game. Simply because it's her specific mechanics that can catch you if you aren't paying attention. Which happens to me a lot lol. But getting that one resplendent spark is worth the trouble. I was able to defeat her in season five with the Lightning Spear sorcerer build. Build, courtesy of maxroll: https://maxroll.gg/d4/build-guides/lightning-spear-sorcerer-guide