My answer today is very different from my answer 20 years ago. There was a time when I loved a good, crunchy RPG, with a ton of splat books and optional rules (in short, Dungeons & Dragons 3.x). Implicit in the crunchiness was a love of customization and the flexibility that came with it.
Now that I’m older — and have a hell of a lot less free time — what interest me is ease of play, flexibility, and a good hook.
Ease of Play
By “ease of play” I mean “how easy is it to play the game?”. The easier it is to play, the more likely I am to run it … but only up to a certain point.
In the past, my group — like me — tended toward more complex games with a lot of fiddly bits (Dungeons & Dragons 3rd Edition, Mutants & Masterminds, Pathfinder, Star Wars: Saga Edition). Today we’ve moved toward more streamlined — but still somewhat crunchy games like Dungeons & Dragons 5th Edition and Savage Worlds. Truly simple games without a lot of crunch likely wouldn’t fly with my group as we do enjoy some degree of complexity … we’re just tired of 3-hour combat encounters.
My group doesn’t venture too far from D&D with our weekly games, so it’s not likely that I’ll buy a game expressly for running with the group. One of those rare games was the new Delta Green RPG. It’s based on Chaosium’s Basic RPG system, so we’re already familiar with the rules and the rules themselves are straightforward.
I’m much more likely to run a non-Dungeons & Dragons game at a convention. For those games, I’m looking for something that’s I can quickly introduce to people. I need to be able to get them up and running within 30 minutes using pregenerated characters, and I need to mechanics to be intuitive enough that we don’t get bogged down in rules as the scenario progresses.
Flexibility is how much the game bends. How much wiggle room do we have within the rules and can they adequately reflect the game we want to run? This includes character customization; I don’t need to get into the weeds of micromanaging skills and capabilities, but I’d like enough flexibility to create characters that are mechanically unique and interesting. This is why the lock-step, “leave no bard behind” progression of D&D 4th Edition didn’t work for many of the players in my group.
For my gaming group, D&D 5th Edition hits the sweet spot for ease of use versus flexibility, but Savage Worlds is a close second.
For convention games, Savage Worlds is my go-to rule set when I’m creating something in a new setting (e.g. my “Savage Stargate” game for MEPACon). I’m familiar enough with the rules to be able to quickly put together player characters and non-player characters and there are enough options there to support a good number of the kinds of games and settings I’m looking to run (superheroes, G.I. Joe clones, weird pirates, etc.). When picking games I might run at a convention, flexibility is still important to me. I like when people can sit down at the table, look over the pregenerated character sheets and see at a glance that there are legitimate different options. While character backgrounds and the act of role-playing itself can help differentiate characters, I like it when game mechanics reinforce those differences.
A Good Hook
A good hook – the aspect that draws you into the game — is perhaps the biggest thing for me. A sufficiently good hook can get me to buy a game even if it’s not a great fit for my group. This includes games like Dungeon World (player-centric world building,) Tales from the Loop (alternating “kids investigating the weird” and “kids dealing with regular life” scene switching) and Blades in the Dark (in media res crime adventures). All of these might be a hard sell for my regular gaming group, but they’re prime convention or online gaming material.
A good hook — be it mechanical or story — might get me to buy the game strictly as a resource and reference. That’s not an ideal reason to buy a game — in a perfect world I’d love to play everything I buy — but sometimes a game is compelling enough to land on my shelf with no chance of ever being run. Dogs in the Vineyard, Burning Wheel, and All Flesh Must Be Eaten all fall into this category of game. I’ve never run them, and likely never will, but I’ve learned from all of them, and that’s helped improve the games I do run.