Spelljammer Ships
Spelljammer: Adventures in Space is a must-buy D&D set because you need magic space boats in your campaign
Spelljammer: Adventures in Space is a massive set of three different supplemental materials for Dungeons and Dragons DMs to explore, and this article will give you some concrete examples of how to use it in your own campaign -- beyond the naturally effusive praise afforded to magic space boats, of course. Spelljammer comes with three books, the adventure Light of Xaryxis -- which, as an adventure, is basically designed for you to use it in a game -- the monster book Boo's Astral Menagerie which by virtue of being a book full of monsters is even easier to use in a campaign, and finally the Astral Adventurer's Guide.