Now you probably think that I'm going to start talking about mechanics here, but I'm not. Because that's not what this is about — for it to be memorable, the mechanics do not matter. Of course, it's easier if the mechanics work, I'm not saying that, but at the end of the day, most people do not remember "Oh I hit the dragon and I dealt 7 damage which killed it." They'll remember "I beheaded the dragon", and that's what we'll be tapping into here.
A well-crafted encounter can make or break an adventure, potentially even a campaign if the players are pissed off enough. (This is where the mechanics DO come into play. Some systems are far better balanced than others. Some don't even have consistency in their own math (I'm looking at you D&D. The fact that I've had to resort to someone having redone your math is annoying)). To create these encounters though, whether balanced or not, you need to take a look at a few things.
Understanding your Audience
First, you need to know what makes your players tick. Taking a leaf out of an author's playbook, you need to understand what resonates with your players in order to craft interesting stories for them to engage with. Your encounters should be tailored to the players' strengths (critically, here I mean players, and not characters), so that there are opportunities for their characters to grow. Some of your players might love tactical combat, some might enjoy puzzles, and others might enjoy straight-up roleplaying and talking. Providing them with these opportunities, perhaps even shining the spotlight on a single character or player in each encounter, will make the experience more enjoyable and immersive for everyone — even if it is a lot of work.
Power of the Narrative
To create a compelling encounter, you need to weave together action and emotion, especially as for many campaigns combat encounters are part of the overarching story (striking down the evil villain for example). You need to consider how each encounter might drive the narrative forward, and provide insight into either the campaign's lore or character development. A good encounter isn't just about rolling the dice, it's about creating a moment that'll drive the plot forward.
I'm going to mention one more thing here, which many authors and designers of TTRPG experiences often forget, but which is an integral part of designing for things like computer games, and that is the power of foreshadowing. Now we all foreshadow the story, but computer game designers often foreshadow individual game bosses and mini-bosses. A good example of this is Molten Core from World of Warcraft. Within the Molten Core instance, there are a number of bosses. The first boss in Molten Core is Lucifron who is a type of salamander called a Flamewaker. When heading to him, you'll encounter a number of other salamanders as well as Core Hounds (multi-headed dogs made of lava), which will give you an introduction to how the mechanics of that boss works, before you even see him. Likewise, the next one, Magmadar (an enormous core hound) will have been introduced in a similar manner. Sometimes this foreshadowing is mechanical, and other times it is visual. But it is always there, and is a great way for you, as a GM, to make your player go "Oh so THAT'S why we ran into so many of X".
Clear Objectives and Motives
Not every encounter needs this, but every boss encounter does. There must be a clear objective (defeat the villain, pull the lever, escape the trap, etc.), and if there is a villain a clear motive for why they are the villain. Sometimes the heroes won't find out, but there should always be a way. It could be a diary, building plans, a servant that's willing to talk, the villain monologuing about their pain — the medium doesn't matter. But the chance of learning more should always be there. Not only is it satisfying for the players and their characters, but it's also satisfying for you as the GM to show off your proud creation. After all, the spotlight is often on you too, so you deserve some satisfaction when gaming as well, it's not all about the players.
Risk & Reward
The most compelling stories come when there is a risk involved in achieving your goal. This is very evident in most books, where the heroes have to overcome great obstacles to achieve their goals (like Odysseus' many trials before getting home), and your encounters should have a similar principle, where they face risks and are rewarded for bravery and resourcefulness. Give them standard treasure for just overcoming them, but give them something extra when they've been smart. Give them a meaningful incentive for going above and beyond, such as valuable loot, important information, or even just the chance to deepen character relationships with each other or the NPCs.
This is where mechanics again come back in. In a book, you can simply go "And then the hero rested and they were fine", but that's not how games work. Pacing, therefore, is important, as every story needs climaxes of excitement, but it also needs valleys of calm. Don't just throw 7 difficult encounters at our players where they have to overcome the same 3 opponents. It's boring, and it'll feel that way to the heroes. Instead, vary the difficulty, the opponents, and the obstacles. Perhaps the first encounter is really tough with 5 opponents, but the one thereafter is a trap, and the third one is a merchant for a social encounter. By varying this, you control the pacing, and you can ensure that your final encounter is the most exciting one and that the players are mentally rested for it.
Surprise and Reinvention
Many authors use unexpected twists, turns, and reinvention to keep their readers hooked. Similarly, you can surprise your players with unique and unconventional encounters. Introduce unexpected elements, like environmental hazards, shifting terrains, or sudden twists in the plot during combat. Reinvent classic monster encounters by adding custom abilities or unexpected allies. These surprises not only keep players engaged but also challenge them to think creatively and strategize in novel ways.
But remember: DON'T OVERDO IT. Sometimes a goblin is just a goblin, and that is fine too. :)
And that brings us to the end of this blog. I hope you've learned something, or at least found it interesting. Combine all these elements and watch your encounters grow more exciting and interesting, making it something your players will talk about in the months and years to come.
See you next week. :)