This article discusses challenge. It also uses a lot of references to creatures in 3.5 Dungeons and Dragons and the Pathfinder RPG as that is the system I am most familiar with. However, hopefully the concepts translate well when thinking about other RPG systems.
There’s an enemy that I don’t believe sees enough play after the earliest levels of Dungeons and Dragons or Pathfinder. That enemy is the basic Orc Warrior, or whatever his equivalent is in other systems. To explain, the Orc Warrior from most d20 games has a challenge rating of one half and, while potentially quite deadly to a group of starting adventurers is usually quickly put aside for bigger enemies. Orcs are not alone in this plight. They share this fate with Goblins, Gnolls, Kobolds… there’s actually a pretty long list. It’s not that creatures of these races never show up at higher levels, it’s just that when they do they usually come with class levels to put them on the player’s level. The idea being that every fight should be challenging to the players, which seems like a good idea in theory but is less so in practice.
I know what you’re thinking: “What do you mean you don’t want every fight to be a challenge?” The answer comes out to scale. If every enemy you fight is the equivalent to your level, then it makes it difficult for players to feel the growth of their characters in experience and power. This is where the Orc Warrior becomes a wonderful tool. By virtue of being likely to be one of the first enemies the players encounter, it gives them an automatic sense of scale. At level one a full party of players might find themselves on the ropes against an equally sized group of Orcs. When level five comes around, and the players are that much stronger, you can put them up against a similar or perhaps even slightly larger group of them. Your players won’t be challenged, but they will feel badass and it will give them a sense of accomplishment. Or, if you feel they SHOULD be challenged in this encounter, have it be by a much larger number of Orcs than before.
This can, of course, be done with more than just groups of Orcs. It can be done with monsters that once terrorized your players. Consider the Ogre or the Troll. Both of these creatures can be nightmares for early level players. An Ogre can be an absolute nightmare at low levels (Such as level 2, where they’re considered a “difficult” challenge) and can even put a party’s fighter on the ground with one lucky swing. So here’s what I want you to imagine: Your party has just made its way through a monster’s den or whatever dungeon and they come face to face with an Ogre. The warrior takes a club to the face early on, putting him into negatives. The cleric moves in to try to heal him while the rogue gets into position to sneak attack. The mage drops a spell, let’s say Ray of Enfeeblement to weaken the massive creature and the Ranger put an arrow into it. On the next round the Ogre hit the Rogue, he’s weakened, and it’s not deadly, but it’s not good either. The cleric steps up to fight and the mage drops another spell, say Grease to make the monster fall allowing the ranger to finish him off within the next round. The players have won the fight but two of them went down and the victory was hard fought. Now imagine that group of Orcs from the last paragraph. Let’s say that, feeling their imminent defeat shortly into the first round they bring out the big guns, the pair of Ogre mercenaries that they’ve hired. Man do these Orcs think they’ve got it made, and your players remember their first encounter with an Ogre. This time, though, the Fighter takes the Ogre’s attack and keeps going, the first Ogre is dead within a round. The second Ogre doesn’t have long before he’s down too, probably from a single failed will or reflex save against a wizard’s spell. The players feel powerful now, even moreso if they remember their first encounter with an Ogre that nearly wiped the party.
Now obviously this doesn’t mean that every fight, or even the majority of fights, should be easy for your players, but if you try to keep a realistic world you have to remember that when your players hit a certain power level, there start to be fewer and fewer things in the world that ARE a realistic challenge so it only makes sense that your characters run into plenty of things that they’re more than capable of defeating easily.
I guess the ultimate point of this post though is this: when your player characters become powerful, it’s important that they FEEL powerful. Sure they can look at their numbers and compare them to weaker enemies, but seeing it and knowing it is very different from feeling it. The other side of this is giving them adequate and impressive big bad guys to fight. This means Dragons, Giants, Demons, that sort of thing. But that’s a subject for another article.