I fully believe that every game system has some idea worth stealing. From D&D 4e, it is the idea of a skill challenge, making multiple skill checks towards a larger goal. However I feel the idea needs refined some and I am going to talk about that here, using my home Pathfinder 2e game as an example.
For the Halloween game I ran this past weekend, the group came across a poltergeist and killed it, but it’s essence returned to it’s chained up coffin. When they discovered it, I gave them these rules:
To put the troubled spirit to rest, you have to perform a ritual. The ritual requires a series of skill checks. The DC of the first check is 20 and increases by 2 for each subsequent check. This continues until you have succeeded or failed 3.
You can use any skill you choose as long as it can be reasonably justified and you describe how you use the skill for the overall ritual. The others in the group can help using the Aid action. However their help requires them to use the same skill check. The DC is the same DC for the main check -4.
However, once you use a skill, you cannot use it again for the entire group.
I will admit that is edited slightly from what I gave them. I made these changes after seeing it in action. Playtesting and all that.
Feel free to use these in your own game. Obviously, adjust the DC to your own game. If you use DC 20 in 5e, it may result in a complete failure. However, if your group is 15th level Pathfinder 2e, they probably have bonuses to skills above 20. The first check should be relatively easy. Everyone in my group had a +13 to at least one skill so they only needed to roll a 7 (without any Aid from others in the group) to pass the check.
Here’s the real kicker though, and I had to point this out to my players so you may need to as well. The DC increases by 2 for each check. So the second is DC 22, third is DC 24, and so on. This means they now we’re looking at which skills that were good but not their best for the first one, saving their better skills for future checks. Now, order mattered.
The adventure itself was a solid one and I might right it up during the next year and release it as a Halloween adventure next year.