Sometimes when you are GMing, scenes end quicker than you expect. The PCs enter the scene, and immediately trigger the exit. In most cases this isn't a problem. You find out what scene they want to do next and make it happen. Ripping through an adventure at warp speed can be fun.
Sometimes it is a problem.
Sometimes a big action scene turns into a yawn.
Maybe the PCs got lucky. Or the players were just that good. Which is wonderful most of the time, but this was the boss you been foreshadowing for four sessions. And the players don't look pumped, they look sad because they were expecting an exciting challenge, and found a marshmallow.
Extending Combat
A major fight that ends in one round feels anti-climatic. Some players won't mind, but many will.
There's a few tricks to keep an important fight going. The trick is to not negate the players' victory, just keep the fun going a while longer.
Reinforcements You already have the stats for your opponents, and as they are mowed down, have more of the same show up. To preserve the player's victory, use less of them, and/or have them show up at some disadvantage.
- The PCs hear the reinforcements coming, allowing them time (1 round!) to prepare.
- The reinforcements have to climb up a ladder to get to the PCs.
- The reinforcements are second stringers, and have less hit points.
- The reinforcements are quick to flee if the PCs are obviously winning. This lets you keep the fight going, but not turn it into a slog.
Fake Boss! The boss you planned for just went down, and then you have the *real* boss you just made up step in to continue the fight. To give the PCs their victory, the first boss drops an important item, something that has "made to fight the next-boss" written all over it. The anti-undead sword-cane of doom, the reveal-invisible dust of St. Silverius, the armor shattering bolt of victory...
Or the victory can be tactical. They have the "real-boss" at a disadvantage, and you give them a bonus to show them that. For example, you could give them advantage in 5E, increment the escalation die in 13th Age, or lower the difficulty for the PCs by 1 in Numenera.
Great, but what is this new boss? Who can make up a boss on the fly? Not me; even in a rules light game like Numenera, a boss should offer unique challenges.
Your choices are to find one quickly or make one quickly.
Find one from an adventure, bestiary, or other game supplement. That could work, but might take a while. What's the next boss you planned on using? Bring them on now? Or a weaker version of the next boss, just add a few weaknesses? This could be good foreshadowing. It helps if the two bosses are thematically related to each other. Cultists to the same dark god, dragons working for the same queen, and so on.
Jack in the Box This is easy and can be a lot of fun for the players. They bring down the demon, and they look at each other. "That was easy." Too easy.
Make one or more creatures get back up after they fall dead. If they are not undead, have them rise as undead. Drop their offensive and defensive powers a notch, give them typical undead features, and resume the battle.
If they are undead, you could make it obvious that a "dark ray came from the unholy altar and when it touched the creature, it jumped up, ready to continue the battle." Now the PCs know they will have to stop the altar from doing that or this could go on and on. Since you just made this up, let whatever crazy idea they come up with work.
I built a Jack in the Box into my 13th Age adventure The Tower in the Mist: Too Easy? Consider Fulvos coming back as a zombie mutant dragon the round after he goes down, with half hit points and -1 on all attacks, defenses, and damage.
13th Age is a high hit points game, so I cut the zombie Fulvos' hit points in half. He's up and undead, just long enough to scare the players and make the encounter fun. And who doesn't like a zombie mutant dragon?
Extending a Chase
Say a big exciting chase is over because your PCs caught the vampire with the horse/Mercedes/hover-bike in the first block, and you wanted it to drag the party to a major plot point that has to be outside town?
You can make the chase continue, but you need to do so in a way you don't negate their victory.
If it's not the vampire itself that's the goal, you could have the creature throw the magic item/deed/holo-chip to a confederate who carries it away. The party still has a high value prisoner, who may have other valuables, and they can follow the confederate.
If the vampire is the goal, you could have it escape at great cost. The PCs might be annoyed they haven't caught it yet, but they've wounded it terribly, and made it drop something valuable. It's keeping its distance, but the PCs know they are winning.
Part II: When Social Scenes End Too Quickly