Adjudicating how much knowledge a character might know about a creature can be somewhat guesswork. Here are some guidelines for what information a character might know about the local monsters and beasts. This is meant to represent a player rolling for the characters general knowledge. Time spent researching could gain information specific answers that would normally be out of their reach.
To help us with this let’s start with something called the ‘Monster frequency encountered percentage’. In previous versions of D&D, each creature in the Monster Manual also came with a frequency encountered percentage. This referred to the likelihood of a particular creature being encountered in an environment where it would inhabit.
Monster Rarity
Common: 65%
Uncommon: 20%
Rare: 11%
Very Rare: 4%
We can then use this guide for how difficult it is to know details about a creature. Chose how rare the creature is to the character considering the places they have spent most of their time.
Common: Creatures that almost everyone in the area have seen or heard about. Typically these are beasts and especially domesticated creatures.
Some examples I have chosen for my worlds Kingdom of Sebal: sheep, cattle, kangaroos, human’s, horses, poisonous snakes, boar, thylacine, echidna, wombat, parrot, magpie, crow.
Uncommon: Rare beasts, reclusive beats and the most common predators of the area.
Some examples I have chosen for my worlds Kingdom of Sebal: Giant fire beetle, Giant frog, Giant thylacine, Giant spider, Giant poisonous Snake
Rare: Predators that need a large hunting area to sustain them, magical creatures, reclusive creatures that can hide easily.
Some examples I have chosen for my worlds Kingdom of Sebal: otyugh, green hag, dryad, shambling mound.
Very Rare: Predators with extremely large hunting grounds typically apex predators, creatures from other planes of existence.
Some examples I have chosen for my worlds Kingdom of Sebal: Wyvern, Stone Giant, Behir
Skills
A suggestion of skills that could be used for knowledge of creatures by type:
Nature: Beast, Dragon, Fey, Giant, Ooze, Nature
Arcana: Aberrations, Construct, Elemental, Monstrosity
Religion: Celestial, Construct, Fiend, Undead
History: Humanoid
Now that we have how rare a creature is and what skill is used to know information about it we can look at what DC’s give us what kind of information.
| Rarity | Base Info | Advanced | In-depth | Expert |
| Common | Automatic | DC 10 | DC 15 | DC 20 |
| Uncommon | DC 5 | DC 10 | DC 15 | DC 20 |
| Rare | DC 15 | DC 18 | DC 21 | DC 24 |
| Very Rare | DC 20 | DC 23 | DC 26 | DC 29 |
Information Gathered
Base information
– What its called
– Creature type eg Beast, Undead etc
– If its a carnivore, herbivore or omnivore
– Environment – what type of environment it normally lives in.
– Primary movement type and speed
– A general idea of its intelligence. Animal, Humanoid, Genius
– Immunities if they are of the following type: piercing, bludgeoning, slashing, fire, lightning, cold. Also, any vulnerabilities that are commonly known as part of a legendary creature such as a vampire vulnerability to sunlight.
– A general idea of what skill the creature is best at. Eg. you would know a Tiger has excellent stealth
Advanced Information
– What it eats
– If it has Resistances if of the following type: piercing, bludgeoning, slashing, fire, lightning, cold, acid
– Secondary movements (eg climb, swim)
– If intelligent a language it is likey to speak or understand
– What repulses or attracts it
– Vulnerabilities if they are of the following type: piercing, bludgeoning, slashing, fire, lightning, cold, acid
– Lair – what type of home it typical makes
– If it can cast spells
– Any conditional immunities
– You know a special attack method of the creature eg: you would know a wolf can pull you to the ground with every hit
In-depth Information
– What other types of creatures it will live with or near
– Immunities of any normal type
– Resistances of any normal type
– What school of magic the creature is known to use of any.
– Vulnerabilities of any normal type
Expert Information
– Specialized unusual methods are required to kill the creature. Eg A lich having phylactery
– Unusual vulnerabilities or immunities eg A Rakasha being vulnerable to magical piercing weapons wielded by Good creatures.
– If a legendary creature a lair action it might have
– 1d4 specific spells they are known to cast if any