Holy Fury is the newest expansion to Crusader Kings II, the celebrated medieval role-playing grand strategy experience from the masters of strategy, Paradox Development Studio. Lean on your war lodge for support in your conquests, bow before the Pope to claim your divine throne or establish a legendary bloodline that will echo through the ages.
Holy Fury is not only a perfect DLC, which improves the game’s balance greatly, but also the best expansion Paradox has ever created. [02/2019, p.50]
A decent entry to a long list of Crusader Kings II DLC. Holy Fury provides a plethora of changes to make your playthroughs more meaningful and dynamic. Sadly, you still need other DLC to make the most out of it.
In a situation where you have all of it, HF is going to truly shine, pulling together parts from four or five different DLC and using them together. If you don't have at least one of Sword of Islam or Rajas of India (and preferably both), you are going to run into a significant amount of frustration, especially in randomized worlds.