How can success and failure on a single action affect the course of the game, without risking bringing everything to an untimely halt?
One possibility is for success to give the persona an advantage on future activities. She can still succeed in those activities even if she fails this roll, but she is more likely to succeed later if she succeeds now. Conversely, failure might impose a disadvantage. Obviously, these two could be combined, to create a really big difference between success and failure on this roll.
This solution has to be used sparingly, for two reasons. First, it is dependent on the possibility of success or failure on the following actions. At some point, there needs to be a task that is performed for its own sake.
Second, it is possible to build up so many advantages or disadvantages on early rolls that the final roll, at what should be the climax, is a foregone conclusion. While that might be realistic, it is not dramatically interesting. Sometimes, of course, the part that sounds like it should be the climax is really part of the epilogue, and the real climax happened earlier in the story. For example, if adventurers brave great perils to claim the Gem of Blasting, which then lets them destroy the army besieging their city, the climax is not the destruction of the army; the climax is seizing the Gem of Blasting. The destruction of the army is just epilogue. Even so, the excessive use of advantages and disadvantages can remove the drama from the actual climax. That needs to be avoided.
A second possibility is for success and failure to change the context of future actions. That is, what you get for success or failure changes. Returning to the Gem of Blasting example, successes and failures earlier in the adventure could determine how quickly you get the gem, which determines how much damage has been done to your city by the time you destroy the besieging army.
Building up a lot of context changes does not make the climactic event easier or harder, so it retains its drama. If it is done carefully, success at the climax is still much better than failure, so the players still want to succeed. However, earlier successes increase the benefits of success and reduce the risks of failure. Absolute failure at the climax is dramatically appropriate, and so can be permitted, but earlier successes might mean that even a failure at the climax permits a degree of success.
The problem with changing the context is that it doesn’t always make sense. Think again about trying to recall a fact. It is hard to see how this would change the context of action, and much easier to see how remembering a fact could grant an advantage. This means that we cannot rely exclusively on this option, either.
Fortunately, we are not required to do so. The core mechanic should be unified, but that does not mean that the meaning of success should always be the same. It is entirely reasonable for a success to sometimes grant a bonus, and sometimes change the context. I intend to use both possibilities in Kannagara, but also the possibility of creating options, which I will discuss in the next post.