Part of how I GM has always revolved around consequences. My default assumption is simple:
“The player characters are the protagonists, and they should be able to inflict significant and long-term changes to the setting.”
This sort of premise places a remarkable amount of responsibility on the players, who must then consider the actions of their characters in order to ensure that the changes that happen to the setting reflect their intentions.
But as a GM, how do you reflect this sort of changing, adaptive world?
In my case, I manifest these changes to the status quo by playing out the consequences. There are a few key things to remember when playing out the consequences of a Character’s actions, no matter if they succeed or fail.
Keep it Immediate – Consequences are felt the moment that they hit. Make sure to not take too long before the consequences of their action are felt. Did they snub an influential Socialite? Have them feel some of the NPCs grow cold or awkward when dealing with them next. Immediate consequences hammer home that something’s changed and that the players should keep their eyes and ears open.
Don’t forget the Long Term – Many people have very long memories about the slights against them, and more than a few people tend to nurse long and vicious grudges. This is the domain of the long term payback from NPCs. Of course, long term consequences aren’t limited to just people. Towns that the characters have saved might flourish, or those that they’ve ignored may become ruins the next time they visit.
Keep it Meaningful – Don’t forget that to a person’s eyes, something becomes apparent if it is felt in a manner that they are aware of. A Merchant will feel it when their profits go down, but might be oblivious to the slight shift in religious doctrine that a Cleric might find as obviously Heretical. When propagating consequences, make sure to coach it in a fashion that the players will notice and care about.
Remember though that consequences aren’t just limited to the actions of NPCs. Consequences could be anything from a shift in economics, a meme, an upheaval in political climate, and countless other things. Ultimately, Players should ideally feel like the world is changing based on their actions. This teaches them a form of accountability, and as long as the consequences keep coming in a fashion that motivates them, then the players will pick themselves up and keep going, knowing that their struggles are far from futile.