Diablo 2: Resurrected is Diablo IV Gold the remake of Diablo 2 and will launch updated to the latest patch of 1.14, which will include many of the revisions and additions. This will also include the Pandemonium Event originally introduced in patch 1.11, the quest that Lilith was introduced in.
Though she appears as a reskinned Andariel, the Act 1 boss in Diablo 2: Resurrected, there is a reason for that. This is because Andariel is referred to as the daughter of Lilith and is a succubus herself, much like how Lilith is the Queen of the Succubi.
Though because the Pandemonium Event is exclusive to Diablo 2's online service, it isn't confirmed that the events during this quest are canon or not. In order for players to access the Pandemonium Event in Diablo 2, they must collect 3 keys, each opening up 1 of 3 random red portals leading to another realm.
One of these red portals leads to the Matron's Den where players will find Lilith, also known as Uber Andariel due to the reskin of the original boss. Lilith, much like the Lesser Evil Andariel, uses poison spray attacks and inflicts heavy poison damage to players so it is recommended to have capped Poison Resistance and Antidote Potions.
Once defeated, she drops Diablo's Horn, 1 of 3 necessary ingredients to access Uber Tristram. The final reward will be buy Diablo 4 Gold a unique Large Charm called the Hellfire Torch, an item that players continue to grind for a perfect one.