Sufficient time has passed for Helldivers 2 players to have found the difficulty that best suits them based on their skills, play style, and time spent playing. There are a total of 9 options and both the icons and the colors make it very clear how much you are going to suffer.
Arrowhead Game Studios has not stopped making adjustments to the difficulties: from tweaks to the patrol system, to the power of enemies, to changing some basic features such as obtaining samples. Until recently, levels 1-5 were used to play relatively calmly, farm credits and have fun without much stress; 6-7 are the middle ground and with 8-9 we talk about hell on earth.
However, a recent update has made Level 6 the perfect difficulty for many players. “Best difficulty where most gear will be viable, you can still fight those big enemies and now you can get ultra rare samples!” says splatbob1 on Reddit. And you're right, since Arrowhead added the ability to get super samples (pink/purple) in a recent update.
The comments agree with you and I think they are right. “Before the update, we usually played 5 for relaxation or 7 for supers” and “As someone who only does difficulty 7 missions, I totally agree with your statement […] Difficulty 6 strikes a great balance.” While most agree that this is the most optimal/balanced difficulty, many prefer Level 7. If you want a medium challenge and super samples, you know where to go.
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