Tabletop RPGs are another way to have fun with your favorite world. Most fandoms have licensed RPG properties, and licensed RPGs can also be a good source of extra worldbuilding tips that can’t be found in the original material.
What do you do, though, if your favorite fandom doesn’t have one? Game design can be complicated, so it’s often easier to choose an existing RPG system and adapt it to your chosen world.
I’m going to talk a bit about the process of doing so by giving examples of systems I would choose for two well-known fandoms.
The first thing to consider is the amount of magic or high technology in the world you’re considering. For example, magic, superpowers, high technology and psionics may all need to be taken into account.
The second thing to consider are your own preferences. Some people enjoy very crunchy systems such as GURPS or Champions. Others would prefer fewer rules. The examples I am going to use lean toward the latter.
If you’ve spent any time at all on Tumblr lately, then you haven’t been able to avoid the rapid rise in popularity of this cartoon. There’s a mobile video game but no tabletop game yet.
For Steven Universe, I would go straight to the Fate Core system. (The pdf version is pay whatever you’d like over at Evil Hat Games.) This is a rules-light system with a few skills that can easily be changed to better fit the universe. Characters are based around aspects, a descriptive phrase attached to him or her, that can be invoked whenever relevant.
In Steven Universe, a character’s gem type could be made an aspect. The character can then do anything with that aspect that makes sense. So, for example, Garnet might have, as her primary aspect, “Always In Charge (And With A Charge)” to reflect both the fact that she’s a leader and uses electrokinesis powers. The advantage of using Fate is that it’s possible to create a character very quickly since everything has an attached aspect—even situations, environments, and consequences. This means that you can simply establish that Sugilite is “A Colossus Who Fights Only For Herself” and that aspect can be brought into play whenever Garnet and Amethyst fuse. The storytelling nature of the system lends itself perfectly to stories about relationships.
Mad Max would work well in the GURPS system, however, my personal recommendation would be Savage Worlds. Savage Worlds is designed to be a generic fantasy system but has a skills system that’s well suited for a post-apocalyptic world. Characters have attributes and skills, and you just roll for both.
Skills are pretty broad. Unlike other systems, Driving would cover everything from a motorcycle to the War Rig. Shooting would cover whatever kind of weapon your character picks up. This means that characters can be as versatile as they were in the recent movie without having to build a complex skills sheet with multiple specialties. Savage Worlds does expect the world to have powers, but those rules can easily be ignored. A Test Drive copy of the rules is free from Pinnacle Entertainment Group, but they charge for the full version.
I hope this brief rundown helps to work out which system might suit the fandom you’re trying to play in, whether it simply doesn’t have a system yet or whether you’ve looked at the licensed product and decided to back away slowly (or run screaming) from its complicated design.