How many liches does your world have?

If you’ve ever given your D&D world serious thought, you have probably, at some point, come up against this conundrum:

Should the world level up with the players?

For example, at 1st level, the adventurers are probably dealing with monsters of CR ¼ and below: goblins, skeletons, giant rats, and so on. Do 20th-level characters encounter such creatures, too? And vice versa: what are the chances of 1st-level characters stumbling upon a lich, or an ancient red dragon?

How you answer this question probably says something about what type of DM you are. If you envision an open world where adventurers can stumble upon all kinds of challenges—some of them deadly—I suspect you are slightly more in line with Old School styles of play. If you prefer your encounters to be carefully balanced and planned, I imagine you are more ‘New School’ (if that’s a thing). Both approaches have merit: one is arguably more realistic and immersive, and the other feels more on the side of the players, avoiding meaningless random deaths. And anyway, I don’t want to set up a false dichotomy. I put the question to Twitter (sorry, Elon, I still can’t say ‘X’), and as I expected, most responses fell somewhere in the middle—although a surprisingly high percentage, nearly a third, said the world should not level up at all.

Should the world level up with the PCs?

— Scroll for Initiative 📜 (@scrollforinit) February 28, 2024

All this gets me thinking about the ecology of my game world, if we can call it that. How rare is an ancient red dragon? A storm giant? A bulette? That’s really what this article is about: trying to find a framework for monster rarity.

In thinking about this, I see a correlation between rarity and challenge rating (CR), just like there is a correlation between magic item rarity and power level. At a certain CR, monsters should be special, legendary, maybe even unique like demon princes and the tarrasque. Conversely, creatures that don’t really pose much of a challenge are ordinary, mundane, even ubiquitous. Maybe I’m wrong to think like that, and my approach is no different to ‘levelling up the world with the players.’ I’m sure someone will tell me so in the comments. But it makes sense to me. Surely there can’t be many wyrmlings that survive into ancient red dragons? Surely there can’t be that many wizards who successfully complete the ritual to become liches?

It also fits with what the core rules have to say about tiers of play (see Chapter 1 of the DMG). At low levels, adventurers are local heroes: ‘they can expect to fight savage orcs, ferocious wolves, giant spiders, evil cultists, bloodthirsty ghouls, and hired thugs.’ At mid levels, they might face ‘savage giants, ferocious hydras, fearless golems, evil yuan-ti, scheming devils, bloodthirsty demons, crafty mind flayers, and drow assassins.’ And it’s only in the very highest tier of play that they face ‘savage balor demons, titans, archdevils, lich archmages,’ and ‘avatars of the gods themselves.’ It’s not that the world levels up: it’s that the world goes bigger, expanding from a local area, to a broader kingdom, to continents, to worlds beyond.

If we re going to link rarity to CR, we might as well use the existing categories for magic items: common, uncommon, rare, very rare, legendary. Instead of artifacts—uniquely powerful items—we might use ‘mythic’ instead. Here’s how I broke it down:

• Common: widespread, ubiquitous. Even Tier 0 adventurers can defeat them. CR ¼ and below. These are generally creatures that can be found more or less anywhere. Even fledgling adventurers can deal with these.
• Uncommon: known, but not routine. Tier 0 adventures might encounter them, but they would still be noteworthy. A fitting challenge for ‘local heroes’ (Tier 1). Perhaps they inhabit specific locations. CR ½ to 5
• Rare: seldom seen; perhaps they inhabit remote or dangerous areas, or they are part of local legends and tales. Probably not encountered until 5th level. Think young dragons. CR 6–12. A fitting challenge for ‘heroes of the realm’ (Tier 2).
• Very rare: not encountered until Tier 3 (11th level). Think adult dragons. CR 13–18. The average person might very well never see one, or even doubt their existence. A fitting challenge for ‘masters of the realm’ (Tier 3): ‘shining examples of courage and determination—true paragons in the world, set well apart from the masses.’
• Legendary: might be seen as early as 14th level, but mainly reserved for Tier 4. Think ancient dragons. CR 19–24. These creatures might be the only one of their kind in the world—certainly rarer than ‘very rare’—and if not unique then certainly immensely significant. This feels right: after all, according to the DMG, ancient dragons are creatures of legend, and only ‘masters of the world’ (Tier 4) can hope to defeat them.
• Mythic: almost certainly unique across the Multiverse, like the Tarrasque. Beyond legendary. CR 25–30. These beings are a challenge even for the most legendary of heroes.

Of course, this is a broadbrush approach, and there are always going to be exceptions. As one on Twitter pointed out (I’m really sorry, but I can’t find the link!), we wouldn’t expect unicorns (CR 5) to be more common than mammoths (CR 6), so an element of common sense needs to be applied. I would maybe suggest that when we’re at the cut-off points between one rarity and the next, beasts and humanoids should maybe slip into the lower category and otherworldly creatures like aberrations, celestial, fey, and fiends can be bumped up in the higher category. Thus, an orc (CR ½) might become ‘common’ rather than ‘uncommon’ while a balor (CR 19) might become legendary rather than ‘very rare’. In essence: use a bit of judgement. Let the lore guide you.

What should you do with this framework? That’s up to you! It’s not something I would ever intend to apply strictly. For me, it’s about your world’s lore and something to have at the back of your mind when you’re coming up with adventure ideas. For example, if I were to use an adult black dragon, it wouldn’t just be a ‘CR 14 chaotic evil huge dragon’ but a named creature whose coming was a once-in-a-generation event. If we think of liches (CR 21) as ‘legendary’ creatures, there might only be a dozen or so in the whole world. The principles of this article would also change how I drew a world map. Rather than just having frost giants (CR 8) as a random wilderness encounter, I would reevaluate them as ‘rare’ and think about the implications of that: I might carve out a particular glacier or mountain to be their hunting grounds, a land spoken of in fear.

So, back to the original question: should the world level up with the players? My answer: it’s something I do my best to avoid. Not only does it make the world less immersive, but it undermines the achievement of reaching high levels (‘hmm, funny how the town guards can suddenly cast fireball, right?’). Instead, as the PCs get more powerful, they should be drawn to more dangerous and otherworldly locations: truly legendary adventure sites on the very edges of the map, or even beyond it. And hopefully this monster framework gives you a way of thinking about how that might work.

How many liches does your world have? What do you think of these CR ranges? Can you see yourself using this approach? Share your thoughts in the comments below.

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