Level and CR Equivalency

One of the patron saints of the D&D 5e renaissance.

OK this is a good one. Lots of DM resources for D&D 5e today. I have an examination of the theory of CR and level, charts compiling disparate information across multiple book sources, and a houserule for playing monster statblocks as PCs! Whew! It's christmas all over again!

One of the things that bothers DMs who get really detailed about encounter design, is that in 5th edition, there is no clear equivalence between level and challenge rating. The challenge ratings given to monsters are vague approximations of how powerful that monster is, compared to a party of 3-5 characters. it is extremely vague and based on subjective experiences during play testing.

This is frustrating, especially for old-schoolers like me, because this wasn't always the case. In OD&D, monsters had levels. Same as characters. Levels were equivalent to HD. It was simple and obvious. Sure, not every level 1 monster was equivalent to every other level 1 monster and level 1 PC, each level represented a general power range with some overlap with the surrounding levels, but that was clear enough from just a few minutes of tinkering.

However, the folks at WotC have heard our cries of woe and dismay, and have put considerable work into creating general guidelines for what defines a CR in terms of raw tangible power. Their guidelines are, honestly, pretty damn good. Never mind the semantics of what an "easy" encounter is versus a "deadly" encounter. If you just gauge it as different levels of threat, from minor to major, it's pretty spot on. More recently, they decided to go into more detail in a publication called Xanathar's Guide to Everything. I, ashamedly, skipped over this section because I was already fed up with their wishy-washy attitude toward CR.

I was wrong to ignore their work.

On XGtE pp.90 there is a series of charts. This is actually one big chart that they decided to present in a broken format. I have reconstructed the whole chart in the following PDF:

Here.

What does this chart tell us? It gives us the actual PC:CR equivalency ratio for any given creature in the game. (Up to level 20. Everything over CR 20 is just fantastical exaggeration)

The most important part of the chart is the section I have highlighted in yellow. Each yellow cell represents a point where a single monster of a given CR is directly equivalent to a single character of a given level. Now, there's a few areas where that turns out to be sort of a range. For example, a level 20 character is apparently equivalent to CRs 7-10. However, when comparing the xp value of single monsters in those CRs, only the CR 10 makes for a medium threat encounter for a level 20 PC. Ergo, a level 20 character is actually equivalent to a CR 10 monster, and the range beneath that is simply due to how wide the threat thresholds are.

This is super important because it allows a DM like myself to do the following:

1. Balance encounters in which NPCs fight other NPCs. 3-way and 4-way battles can now be calculated. Want the PCs to stumble into a brawl between drow and illithid factions? Go for it! Now you know how many drow need to be in the opposing force to make it a convincing fight! Now you can gauge what kind of a threat a behir is to any given type of dragon! You can present, in combat, the ecology of the D&D world.
2. Determine the encounter budget thresholds for a party that includes NPCs. Simply find the NPC's level equivalent, and add its thresholds to the party threshold totals. Now when you plan a hard encounter against a party with 4 veterans in tow, their power can be accounted for. (Specifically, if each veteran is CR 3, they are each equal to a level 7 character. With 4 veterans assisting the PCs, the threat thresholds would increase by 1400xp for easy, 3000xp for medium, 4400xp for hard, and 6800 for deadly.)
3. Calculate XP rewards for PVP, and for combat against creatures with class levels. For example, if I were to make an evil cleric by giving class levels to the commoner statblock, how much XP is that villain worth when they defeat him? Well, if he's a level 5 cleric, he's equivalent to a CR 2 monster, and is therefore worth 450xp.
4. Determine whether it is appropriate for an NPC to become a hireling for a party of a given APL. Because it is now possible to place monsters as belonging to a specofoc tier of play, it is also possible to do the same with NPCs. For example, given that a veteran is equal to a level 7 PC, that makes it a 2nd tier creature. It would be inappropriate for characters below the 5th level to be able to employ a veteran as a hireling.
5. Allow players to control monsters. Ever wanted to run a Council of Wyrms type game where the players are all dragons? Now you can! Ever wanted to play a zombie? Now you can! This chart can be used to balance encounters for players who are using monster statblocks instead of PCs. In addition, it can be used to find the implicit Level Adjustment for any given monster. For those not in-the-know, level adjustment was a mechanic in 3.5e which allowed players of monsters to accumulate xp until they reached a certain level before gaining any class levels. It was a way of balancing monsters in the party. For example, if I wanted to play an Illithid, I would want to know how many levels of XP it would need to accumulate before it can take class levels. A CR7 illithid is equivalent to a level 15 character. So, upon attaining enough XP to reach level 15, it would finally be class-level 0. It would thereafter gain XP as a PC and gain levels normally. Additionally, for any encounter against a party including this monster, the threat thresholds would increase by 1400xp for easy, 2800xp for medium, 4300xp for hard, and 6400xp for deadly. As a consequence, it would be inappropriate to allow such a character to join the party until their average party level was within tier 3 prior to his inclusion.

Level Adjustment Houserule

For anyone who's interested in allowing players to use monsters in the place of PCs using this level adjustment system, I've done some precalculations for you! When a player chooses a monster of a given CR, simply start that character at negative xp based on the following chart. Once the character reaches 0xp, they can take their first class level.

Monsters beyond CR10 cannot be used as player characters, as their level adjustment exceeds the level limit for player characters. I would not recommend using monsters below 1/4 CR, as they are technically not even worth a single level 1 PC. Also note that a CR 10 monster, though playable in the 4th tier, is not able to gain any class levels whatsoever.

If you are starting the monstrous character in a party of a level greater than 1, give the monster XP equal to that required to meat the pary's APL. For example, if you were adding a CR2 monster to a party with an APL of 7, you would give them 23,000xp., (Leaving them with +9,000xp, and still needing another 5,000xp to gain their 1st class level.)

I have also given the tier for which the character is most appropriate. It is inappropriate to introduce a character to a party with an APL that does not match its tier. If you're the kind of DM who happily runs with wild level disparity, you can ignore this column.

Additionally, a monster's maximum level is equal to 20 minus their level adjustment. This adjustment is meant to prevent a creature from exceeding the total power output of a level 20 character by deducting the power of the base creature from their maximum level. I have calculated that for you as well.

Finally, any monstrous PC must have an INT score greater than 2 and the ability to speak at least 1 language. If a creature does not meet these minimum requirements, the player can play an enlightened version with an INT of 3 and the ability to speak 1 common language of their choice.

CR LA XP Penalty Tier Max Level

1/4 1 -300 1 19
1/2 2 -900 1 18
1 4 -6,500 1 16
2 5 -14,000 2 15
3 8 -34,000 2 13
4 9 -64,000 2 11
5 12 -120,000 3 8
6 13 -140,000 3 7
7 15 -195,000 3 5
8 17 -265,000 4 3
9 19 -355,000 4 1
10 20 - 4 0

When building encounters against a party that includes a level adjusted character, you need to find that character's effective level. Effective level is simply their level adjustment added together with their class level. This will tell you their threat threshold and adventuring day budget.

Neat stuff for anyone who isn't afraid of some extra paper work.