Hell (difficulty)

From Diablo Wiki

Hell is the highest difficulty level following Nightmare in Diablo 2. Although you will have the creatures with the same appearance and the same quests as in Normal and Nightmare, they will be much harder and a few might use more spells.

For having access to the Hell difficulty you must meet one of the following requirements:

• If you are playing an expansion character, you must have defeated Baal at Nightmare difficulty.
• If you are playing a non-expansion character, you must have defeated Diablo at Nightmare difficulty.

Hell difficulty is the only difficulty level in which the two Battle.net only quests, the Pandemonium Event and the Uber Diablo Quest can be obtained.

It is commonly the difficulty where players above level 25 Chaos before reaching level 50 to be able to do Baal runs until they reach a desired level.

Difficulties
Normal • Nightmare • Hell