D&D historian Shannon Appelcline said it best in his description of the 4e DMG on the DMs Guild: But why should you hunt down a book for an edition of D&D you don’t even play? Simple: the lion’s share of this book doesn’t care what edition of D&D you’re playing, and just wants to make you a better Dungeon Master. The current edition of the Dungeon Master’s Guide is a great tool, but as far as learning how to be a good Dungeon Master, you can’t beat the 4th edition DMG. If you play D&D, you should own a copy of the 4th edition Dungeon Master’s Guide.
