In Riders, you have been chosen by the Four Horseman of the Apocalypse to observe events and signs that will help bring about the end of the world. However, you live on the world. All your stuff is there. So, instead, you are trying to change those events and keep the end times from coming.
The driving force behind the overall plot of the game is the Doom Clock. It starts at 5 to midnight. The players are literally struggling to push the clock back seconds at a time. If it gets as far back is 10 to midnight, The four Horsemen decide it's not time yet and go away. If it hits midnight, well, the world ends. Messily.
Adventures are called chapters, which started out with a ritual that both gives you clues to the event you need to change and helps hide you from the eyes of the Metatron, the voice of God who is keeping track of all these signs. They end with you having an actual fight with the Doom Clock.
The rules state that a chapter should take about six sessions and you should have an off session after that about the characters' lives when they're not there busy trying to save the world. And any given chapter is really only going to shift the clock a certain number of seconds.
Now, I have played a number of indie games and I have read a whole lot more of them. As a rule of thumb, I have found that they're designed for relatively short campaigns or even just one shots. Riders is different because it is clearly designed for the long-haul. Yes, there is a definite end in sight, one way or the other, but it'll take you a while to get there.
That means that I'm not likely to play this game anytime in the foreseeable future. However, I like the fact that it really is designed for a longer game with a lot of character development.
What really took me about the game is the concept and setting. It's definitely an interesting idea, maybe a little bit heavy on the sympathy for the devil for my taste, but it is an engaging world. The alternate character templates, if you choose not to be one of the riders, are both interesting and add depth to the setting. In particular, you can be a normal person who accidentally got a page out of the Metatron's notebook.
So here's my problem. Riders doesn't have nearly enough setting information to satisfy me. The designer intentionally kept things vague so that folks could develop the world in the wrong ways. And I am normally really all for that free-form, sandbox approach. My favorite dungeons and dragons campaigns have been in homebrew settings. However, Riders has a very specific structure and I think a more developed setting would be helpful for that.
And, really, I just want more. I thought this was a really interesting take on Biblical End times and I really wanted to see more. I like reading RPG's for fun and reading more about the setting would've been a lot of fun.
Oh, mechanics. Riders uses what is clearly an Apocalypse World influenced system with the addition of a potent but restricted bonus dice. Having had some decent experience with this kind of system, I know that it will work well. Still, if you just gave me the mechanics without the setting, it wouldn't even be a blip on my radar.
I enjoyed reading Riders and I thought that it was a really interesting take on the end of the world. However, I really wanted so much more. It gave me enough to be interested but not enough to get excited.