Casters are going to have an easy time recognizing spells they personally know, so any caster can automatically identify spells on their list. Spells they don’t know, either because they aren’t high enough level or because they have a limited number of spells learned per level (or because they aren’t a caster at all), are the realm of Arcana checks.
DC 5: Recall the existence of the outer planes and that arcane and divine magic are different.
DC 10: Recall the names and basic natures of each of the planes, know the difference between demons and devils, recall the eight different schools of arcane magic and the eight major domains of divine magic (don’t forget the Death domain from the DMG!), recognize a specific cantrip, 1st, or 2nd level spell.
DC 15: Recall major landmarks of a specific otherworldly plane, like the City of Brass in the Plane of Fire, identify a specific type of outsider like an ice devil or a famous individual outsider like Orcus, recognize a 3rd or 4th level spell.
DC 20: Recall specific details about major landmarks of a specific otherworldly plane, like the street layout of the City of Brass, identify a high-ranking individual outsider like a specific balor or marilith, recognize a 5th or 6th level spell.
DC 25: Create a complete map of an otherworldly plane including all major landmarks and most minor ones such that it could be used to navigate the plane, recognize a 7th or 8th level spell.
DC 30: Create a complete and detailed map of an otherworldly plane including all major and local landmarks, including many secret ones, recognize a 9th level spell.
DC 35: Intimate familiarity with an otherworldly plane’s structure (or lack thereof) such that even very local and obscure customs and secrets are known to you.
A DC 15 Arcana check to recognize an outsider works as though it were a successful History check to identify the capabilities of any celestial, construct, elemental, fiend, or undead (not all of these are outsiders, but they are made of or run on magic and have the same DC).
One of the best uses for History is to identify the capabilities and weaknesses of an unknown monster. A successful identification check means the players are essentially allowed to read the Monster Manual entry for the default monster. So, if players roll a successful History check on a named orc Barbarian, they get the Monster Manual entry for a regular orc. If the orc is particularly famous, he can be identified with a DC 15 check (as an important figure of the region), and if he is only moderately famous, he can be identified with a DC 20 check (as a minor figure of the area). Otherwise, all they get is the stat block for a regular orc, even though a specific named orc’s stat block may be radically different.
DC 5: Identify a humanoid. Recall the name of the city you’re from.
DC 10: Recall the capabilities of a beast, humanoid, or plant. Recall the major nations of the area, their most prominent ruling figures, who they get along with, who they don’t get along with, and the nominal reason why they do or don’t get along with one another. Be aware of recent events as known by the general public.
DC 15: Recall the capabilities of a specific humanoid tradition (like the Shadow Thieves of Amn) or of a dragon, giant, monstrosity, ooze, or undead. Recall the basic histories of the major nations of the area, including important figures by name and events by date, and including a basic grasp of how one thing led to another. Have a general idea of the major ages of the world at large and the names of important nations from far away.
DC 20: Recall the capabilities of an aberration, celestial, construct, elemental, fey, or fiend. Have a thorough and in-depth knowledge of a specific period, like a war or a renaissance or a golden age, such that you could write an entire book on the subject, including an analysis of why things happened the way they did. Recall obscure historical facts about minor figures or time periods of the area.
DC +5*: Recall something to do with a distant or hostile region, with which there is relatively little exchange of ideas, like someone from the Sword Coast recalling historical facts from the Moonsea, Thay, or the Underdark.
DC +10*: Recall something to do with an extremely distant region, with which there is almost no exchange of ideas, like someone from the Sword Coast recalling historical facts from Kara Tur.
DC +5: Recall something from an ancient age, which has little connection to modern politics and from which relatively few pieces of historical information have survived intact, like a modern day inhabitant of the Sword Coast recalling something from the age of Netheril or earlier.
*These two are mutually exclusive, so one modifier or the other will apply, not both. They do stack with the other modifier, however, for a maximum possible DC of 35 for recalling obscure historical facts about distant lands to do with another age. All of these can apply to identifying monsters as well as to recalling facts, if the monster appears only in distant lands or if they’ve been unheard of since ancient times (or both). The DC is not increased for identifying a monster who lives in a distant land if other monsters like it live in a land the character is familiar with. A character from the Sword Coast can identify an orc from Thar in the Moonsea region just as easily as he could an orc of the Many Arrows Kingdom of his home. They’re both orcs, and he is familiar with orcs.
In addition to the CSI: Camelot shenanigans you can get up to in the below chart, you can also use Investigation in place of any other INT-based skill provided you have source material to scour through, and that this source material does actually contain what you’re looking for. A single history book probably doesn’t contain enough material to answer any higher than a DC 15 History check no matter how good your Investigation is, but your ability to research questions in a hidden cathedral-library of Vecna is limited only by your own abilities.
DC 5: Yep, it’s wood.
DC 10: Determine whether a wound was from a slashing or piercing weapon. Scan a single small area, like one table, for clues.
DC 15: Determine exactly what sort of weapon dealt a wound. Scan a small shop or one room of a tavern for clues.
DC 20: Recreate who was standing where when a wound was dealt based on footprints, blood splatters, and the position of the corpse. Scan a small building, like a tavern or a guardhouse, for clues.
DC 25: Determine the race (orc, elf, etc.) of a victim from only their blood splatters and footprints. Scan a large building, like a marketplace or a castle, for clues.
DC 30: Discern the difference between riverbank mud and mud from a road further inland, thus proving that the suspect’s alibi about being at the riverbank at the time of a murder is a lie.
+5 DC: While scanning for clues, discover clues which are not obvious, like a murder weapon that’s been intentionally hidden.
+5 DC: Scan an area for clues even if it is very cluttered and poorly organized, like the scene of a violent altercation or a poorly kept library with books constantly misfiled and left strewn about.
In order to sort terrain types by similarity, I have created the following list for use with this skill.
DC 5: You know the order of the seasons.
DC 10: You can identify basic animal types, like wolves, bears, cows, rabbits, etc. etc. You know the difference between temperate forests and pine forests.
DC 15: You can identify specific animals like the difference between a black bear and a brown bear. You know what different animals eat and how basic food chains work.
DC 20: You know the details of the specific terrain type near where you live, including how the food chain works, what creatures live there and how to avoid trouble with them, and the uses of different parts of them, including monstrosities.
DC 25: You know the details terrain types similar to the one you are from. Similar terrain types are terrain types which are adjacent to your home terrain on the list above.
DC 30: You know the details of all terrain types.
DC 35: You know the details of even the most obscure creatures, with an exhaustive knowledge of every kind of bird or bug to ever walk the earth or fly the sky, in addition to the larger and more well known creatures.
A successful Nature check to identify an animal provides the same benefits of a successful History check to recognize the capabilities of a beast, monstrosity, or plant. The Nature check may have a higher or lower DC depending on your familiarity with the climate in which the creature lives.
DC 5: You are aware of the concept of “praying.”
DC 10: You can identify most of the major gods and their symbols.
DC 15: You know all the major gods and their symbols, and you know their rites and rituals for things like marriage, birth, and funerary services.
DC 20: You know the meaning behind different religions’ major rituals, and you’re familiar with the doctrinal disputes that exist or have existed within the religion.
DC 25: You have the scripture of a specific religion completely memorized.
+5 DC: The religion is intentionally secretive, like the cult of Vecna.
+5 DC: The religion is small, like the worshipers of a minor god or demi-god.
WIS: Animal Handling
In addition to the commands below for tamed mounts and tamed animals, Animal Handling can also be used for social encounters with non-sentient animals. We’ll discuss that more in the encounters section.
DC 5: Remain in the saddle while horse is walking.
DC 10: Remain in the saddle while horse is trotting (standard move action), command a tamed animal to follow instructions, tame a mundane beast (dog, cat, horse).
DC 15: Remain in the saddle while horse is galloping (dash action) or jumping (athletics checks), command a tamed animal to follow instructions in a hazardous situation, tame a wild beast (wolf, bear, elephant), attack simultaneously with mount with disadvantage.
DC 20: Remain in the saddle while mount is flying or attacking, tame a monstrosity.
DC 25: Attack simultaneously with mount without disadvantage.
+5 DC: Target animal is unfriendly.
+5 DC: Target animal is hostile.
The border between a mundane beast and a wild beast is not as clear as the border between a beast and a monstrosity. A beast whose CR is at least 1 is almost definitely wild, but otherwise this is a question of whether it’s a farm animal (mundane) or a circus animal (wild).
Also, taking 10 should generally be allowed for anything to do with a mount or animal companion. It’s one thing to require someone to have decent WIS and a relevant proficiency to get their animal companion to attack in combat (DC 15) and quite another to give them a 45% failure rate even when they do.
Like Stealth, Insight is only ever rolled as an opposed check and thus is mostly covered by its description in the PHB (though it doesn’t get its own sidebar) and the Let it Ride advice above. We’ll have more details on how to run a social encounter in the Art of Encounters.
DC 5: Identify sneezing as symptomatic of some kind of illness.
DC 10: Staunch bleeding wounds to stabilize a dying character.
DC 15: Diagnose and treat a common illness like filth fever or the shakes.
DC 20: Diagnose and treat an uncommon illness like plague, cackle fever, or blinding sickness.
DC 25: Diagnose and treat an especially virulent illness like demon fever or devil chills.
DC 30: Halt the progress of mummy rot for a day.
+5 DC: Treat an illness without the appropriate herbs and medicines.
An herbalist kit check of the same DC can be used to attempt to prepare proper medicines and avoid the +5 DC. You also take a bonus to the Medicine check equal to +1 for every two points by which an herbalist kit check to concoct medicine exceeds the DC.
Perception is almost always used passively. Essentially, characters are taking 10 on Perception basically all the time. Objects that can be spotted by their passive perception are spotted. Objects which can’t be, aren’t. Characters rolling Stealth or Sleight of Hand will use the passive perception as a DC, as is described in the PHB.
DC 5: Spot a door. Not a hidden door, just, like, a door.
DC 10: Spot a specific object in a moderately cluttered environment.
DC 15: Spot a concealed door, pit trap, or pressure plate with a slightly noticeable seam or a specific object in a very cluttered environment.
DC 20: Spot an expertly concealed door, pit trap, or pressure plate, camouflaged into the surrounding environment.
DC 25: Spot scuff marks on a shop floor that reveal that someone has been here recently or some similarly tiny and unassuming detail.
DC 30: See an invisible creature based on the displacement of tiny amounts of dust on what appears to be a swept floor.
DC +5: Spot something from 50 or more feet away.
Survival difficulties depend heavily on what the terrain and biome is like, which have been split up (like Nature) by Druid circles. Druids who have a circle gain advantage on Survival checks made in that circle.
DC 5: Find food for a party of six in a restaurant.
DC 10: Navigate in a grassland or coast.
DC 15: Find food and shelter for a party of six in a forest, coast, mountain, or grassland outside of winter, navigate in a forest, mountain, arctic, or desert area.
DC 20: Find food and shelter for a party of six in a swamp, the Underdark, or in a forest, coast, mountain, or grassland during winter, navigate a swamp or the Underdark.
DC 25: Find food and shelter for a party of six in a desert or arctic region.
DC +5: Find food and shelter for 7-25 people.
DC +5: Find food and shelter for each additional 25 people after the first 25.
Arctic: DC 15 navigation, DC 25 survival
Coast: DC 10 navigation, DC 15 survival, DC 20 in winter
Desert: DC 10 navigation, DC 25 survival
Forest: DC 15 navigation, DC 15 survival, DC 20 in winter
Grassland: DC 10 navigation, DC 15 survival, DC 20 in winter
Mountain: DC 15 navigation, DC 15 survival, DC 20 in winter
Swamp: DC 20 navigation, DC 20 survival
Underdark: DC 20 navigation, DC 20 survival