Introduction
Because the SRD only contains a subset of the monsters available in 5e, this data is woefully inadequate. There are large CR gaps where we don’t have data at all. Monster design has evolved somewhat since 5e’s 2014 launch, so these numbers don’t perfectly reflect today’s landscape. Even worse, we have no SRD monsters at CR 18 or from CR 25 through 29, so there are huge gaps in the data, and some CRs are represented by a single creature.
Still, this is the best we can do without getting into dubious legal territory, and the analysis is still informative, especially since the monsters in the SRD are still some of the most commonly used in published adventures. The tables and charts below will run from CR 0 to CR 23, which is roughly where the useful data ends. The Tarrasque, our only CR 30 example, is not a good sample of CR 30 creatures, which are often things like deities.
The Prevalence of Multiattack
Multiattack exists across the full CR scale, but it begins to appear more heavily as CR progresses.
This is a spot where the limited scope of the SRD presents issues because the sample size is so small, but the near omnipresence of multiattack does help us evaluate options like Defensive Duelist and Heavy Armor Master.
Damage Resistances
Prevalence of Resistances and Immunities
The total count of resistances and immunities on a typical creature rises to around 2 at CR 3 or 4, and basically stays there. There is some fluctuation in the data due to outliers and small sample sizes, but the numbers generally stay just above 2.
Damage Vulnerabilities
Hitting a creature’s damage vulnerability is like striking gold, and it’s roughly as likely to happen. Vulnerabilities exist, but according to the DMG monster creation rules, 5e’s philosophy is that they should be extremely rare. The numbers support this.
Most and Least Common Damage Vulnerabilities / Resistances / Immunities
The common wisdom is that Poison is the most common resistance/immunity, followed by fire, and the numbers confirm that thinking. Poison resistance is surprisingly rare, but immunity is extremely common. Poison immunity is more common than the sum of resistance and immunity for any other damage type, confirming the thinking that poison damage is awful for players.
Fire immunity is the second most common immunity, and the sum of resistance and immunity is the second highest. However, fire is also the most common vulnerability. It’s still not common at just 7 vulnerable monsters, but it’s there.
Of weapon damage types, the only vulnerability is bludgeoning damage. The sum of resistance and immunity to weapon damage types is roughly even at 8 or 9, and those resistances come almost entirely from swarms. This means that bludgeoning weapons (warhammers, mauls, unarmed strikes) have a slight edge over piercing and slashing damage. I blame skeletons.
Force damage is essentially a non-entity in the damage responses. Resistance and immunity to force damage is nearly unheard of in the full Monster Manual, so this isn’t surprising. This confirms that force damage is among the best damage types, though magical weapon damage is close behind since it’s resistence almost exclusively by swarms.
For spellcasters relying on elemental damage types, acid is the most reliable, followed by lightning. Cold damage beats fire, but the sum of resistance and immunity to cold is more than double that of acid, so there’s a huge gap.
| Damage Type | Vulnerability | Resistance | Immunity | Resistance + Immunity |
|---|---|---|---|---|
| Non-Magic B/P/S | 0 | 12 | 7 | 19 |
| Bludgeoning | 4 | 8 | 0 | 8 |
| Piercing | 0 | 9 | 0 | 9 |
| Slashing | 0 | 6 | 2 | 8 |
| Acid | 0 | 8 | 11 | 19 |
| Cold | 2 | 26 | 15 | 41 |
| Fire | 7 | 17 | 35 | 52 |
| Force | 0 | 0 | 0 | 0 |
| Lightning | 0 | 15 | 17 | 32 |
| Necrotic | 0 | 6 | 7 | 13 |
| Poison | 0 | 3 | 63 | 66 |
| Radiant | 1 | 4 | 0 | 4 |
| Psychic | 0 | 0 | 9 | 9 |
| Thunder | 1 | 6 | 2 | 8 |
Saving Throws
RPGBOT has long espoused the idea that Constitution saves are consistently high, while Intelligence saves are consistently very low. This has been largely anecdotal and based on spot-checking monster stat blocks, but with real numbers to look at we can see exactly how big the disparity is.
Constitution saves start high, and remain high through the whole CR range, dipping below other saves only in cases where the data is skewed by a tiny sample size or a statistical outlier. Conversely, Intelligence saves start low, don’t hit +0 on average until CR 6, and then remain the lowest save for most of the CR range, occasionally jumping above Dexterity.
Neither of those things are surprising. What is surprising is how low Dexterity saves are. At low CRs, Dexterity is one of the higher saves, but average modifiers stay flat until around CR 5, after which they begin to improve. However, they stay barely ahead of Intelligence saves, even dipping below Intelligence at a few points, though this is likely due to our tiny sample size.
This has astounding implications for blaster casters. An average d20 roll of 10.5 plus the average Dexterity modifier is consistently below the expected save DC for a spellcaster maximizing their spellcasting ability score. While we can’t draw perfect conclusions due to our small sample size, this could mean that targeting Dexterity saves is consistently effective across the full CR range.
The number of saving throw proficiencies also increases over time, which means that creatures have fewer gaps in their defenses. This, coupled with the rising average value of save modifiers, means that players relying on save DCs need to be careful to identify and target enemies’ weakest saves if they want to be successful.
Other Stats
Ability Scores
Ability scores are not explicitly tied to CR, but creatures do generally have better ability scores as CR increases. Strength and Constitution outpace other ability scores around CR 2, and stay considerably above other ability scores for the full CR range. It’s possible that this is due to the poor sample size available in the SRD, but it does still indicate that melee monsters are more reliant on their ability scores than other creatures.
Hit Dice Count
While building the Monsterizer, I often asked myself “how many hit dice should creatures have?” That data point is entirely missing from the monster creation rules because the final number of hit points is what actually matters. Hit dice really only matter for short rests, and monsters typically don’t take rests in a way that tracking hit dice matters. Despite that, we do still see a mostly linear progression of how many hit dice creatures have as CR increases.
What Players Should Learn
- Poison damage is awful.
- Magical weapon damage is nearly unstoppable. Magical bludgeoning damage is the second best damage type in the game, so grab a bludgeoning damage if it doesn’t otherwise hurt your build.
- Blast casters work reliably since average enemies have a less than 50% chance to save against your spells. Force damage, magical b/p/s, acid damage, and lightning the damage are most effective damae types, in that order.
- When targeting saving throws with no other knowledge of the creature, Intelligence saves are always the safest option, followed by Dexterity saves. Strength and Constitution saves should be avoided unless you know something about your target’s stats.
- As you gain levels, higher-CR enemies are more likely to be proficient in saving throws, so you need to put more thought into targeting enemies’ weak saves.
What DMs Should Learn
- When designing monsters, damage vulnerabilities are intentionally rare.
- Hit dice count is mostly arbitrary.
- Monsters nearly always have multiple weak saving throws, and your players should try to target them. If they do not, spellcasters will struggle.
