Let's face it, DM's gotta make calls about what is happening or will happen that preserve the verisimilitude of a fantastic reality. One of the best ways to help with that is to have a vast wealth of knowledge of how things work. Reading is of course a good way, but for my money the best knowledge to time ratio may be found in the frames of Connections. The playlist below starts with the 8th episode of the 1st series, because it has some good information on polearms that will hit you square in the garygygaxes of your heart.
Obligitory links to series 2 and 3
Fun DCCish type jobs and suffering can be found in the frames of another series, The Worst Jobs in History. I don't like the production values or the host nearly as much as Connections, but it was still pretty fun and taught me all sorts of uses for urine.
This playlist starts in the Dark Ages episode.
Now that you got those series taking care of some of your trivial knowledge, you can devote your reading time to fantastic magic rules and monsters, like those presented in Tales of the Dying Earth or Planet of Adventure.
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