There are a lot of RPGs out there that provide very useful resources.
I think I’ll go with D&D 5th edition. The Dungeon Master’s Guide is an incredible book full of really helpful tools for GMs new and old. I believe I haven’t fully utilized it yet and, whenever I browse it, I keep finding new things I didn’t know it contained.
I’d also like to give an honorable mention to Pathfinder and Open Legend RPG. The Pathfinder Game Mastery Guide and the Open Legend Core Rule Book contain a lot of useful information for GMS.
And that’s my answer to today’s question. I’d like your opinion on this. I’m always open to suggestions for useful resources.
Tomorrow’s question is “What are your essential tools for good gaming?”. I think I like this question.
So until then, have fun!