1. Bash Barbarian
This build focuses on high DPS and survivability, making it suitable for taking on Uber Lilith.
Gear
Helm: Harlequin Crest
Armor: Undying Aspect
Gloves: Paingorger's Gauntlets
Pants: Aspect of Might
Boots: Hectic Aspect
Amulet: Aspect of Adaptability
Rings: Aspect of Inner Calm, Aspect of Elements
Main Weapon: Aspect of the Moonrise
Slashing Weapon: Rapid Aspect
Dual-wield Weapon: Edgemaster's Aspect, Aspect of Berserk Ripping
Skill Trees
Basic: 5 Bash (Enhanced, Combat)
Core: 1 Hammer of the Ancients (Enhanced, Violent)
Defensive: 1 Rallying Cry (Enhanced, Strategic), 3 Imposing Presence, 3 Martial Vigor, 1 Outburst, 1 Tough as Nails
Brawling: 5 War Cry (Enhanced), 3 Booming Voice, 3 Aggressive Resistance
Weapon Mastery: 1 Steel Grasp (Enhanced, Fighter's), 3 Pit Fighter, 2 No Mercy, 3 Slaying Strike, 1 Thick Skin, 3 Counteroffensive
Ultimate: 1 Call of the Ancients (Prime, Supreme), 2 Heavy Handed, 3 Wallop
Key Passive: Unconstrained
2. Golem Necromancer
This build focuses on summoning minions and dealing burst damage to quickly defeat Uber Lilith.
Gear
Helm: Blood Getter's Doom Casque
Armor: Adventurer's Tunic of Hardened Bones
Gloves: Sovereign Vambraces of Grasping Veins
Pants: Primal Chausses of Occult Dominion
Boots: Aphotic Warlord Boots
Amulet: Unyielding Commander's Amulet
Rings: Band of Reanimation, Circle of Frenzied Dead
Main Weapon: Blighted Dragon Spine
Skill Trees
Basic: 1 Reap (Enhanced)
Core: 1 Blight (Enhanced, Supernatural), 3 Hewed Flesh
Macabre: 4 Blood Mist (Enhanced, Ghastly), 3 Spiked Armor, 3 Skeletal Warrior Mastery, 1 Grim Harvest, 3 Fueled by Death
Curse Skills: 1 Decrepify (Enhanced, Abhorrent), 3 Amplify Damage, 3 Death's Embrace, 3 Death's Approach, 3 Skeletal Mage Mastery
Corpse: Corpse Tendrils (Enhanced, Plagued), 3 Necroic Carapace
Ultimate: 1 Army of the Dead (Prime, Supreme), 3 Inspiring Leader, 7 Hellbent Commander, 6 Golem Mastery
These builds should give you a solid foundation to tackle Uber Lilith in Diablo 4 Season 4. Adjustments can be made based on your playstyle and available Diablo 4 gold and gear. Good luck!