I wrote a similar article to this on Pathfinder, and though this is a pretty evil topic, it has been of use to a lot of folks out there. So, now, I think, is the time to start a similar article for D&D 5e. This will be a living document to be updated with suggestions and more information as I find better methods. In general, 5e is a lot more challenging for a GM, because the classes are reasonably balanced and because the game mechanics don't have a lot of scale over the 20 levels. Here's a general list of things to increase the difficulty for the party: Increase the number of foes and the CR (ignore the book CR system if it isn't offering a challenge) Spells against the PCs low saves. A high level sleep spell, for example, could take out a party with no elves. Drag out the opportunity for the long rest. After 2 short rests, the 3rd battle of the day is tough. Hit the most vulnerable PC first. It almost always forces another teammate to take an acti...
Chronicles of an Elder GM Running, Hacking, and Sharing Advice on TTRPGs