---
title: 'HOSR Core Rules: Adventuring'
description:
date_pub: 2023-04-26T23:02:00-04:00
section: rules
content_type: feature
short_code: uha
---

[[toc]]

### Ability Checks

Simple tasks are assumed to succeed. If the task is dangerous or complicated, roll the dice for an Ability Check.

-   For most checks, roll a 20-sided die (d20) **at or over** the specified Difficulty Class (DC) for that ability.

-   For harder tasks, add 1-4 to the DC before the die is thrown.

<div class="dividedTableWrapper">

| Ability<br />Score | Roll<br />Bonus | Base DC |
| ^^ | ^^ | ^^ |
| :-: | :-: | :-: |
| 18 | +3 | 6 |
| 17 | +2 | 6 |
| 16 | +2 | 7 |
| 15 | +1 | 7 |
| 14 | +1 | 8 |
| 13 | +1 | 9 |
| 12 | +0 | 9 |
| 11 | +0 | 10 |
| 10 | +0 | 11 |
| 9 | +0 | 12 |
| 8 | -1 | 12 |
| 7 | -1 | 13 |
| 6 | -1 | 14 |
| 5 | -2 | 14 |
| 4 | -2 | 15 |
| 3 | -3 | 15 |

[Ability Check Roll Bonus and DC]

</div>

-   Some results are special:

    -   A natural 20 represents a critical success: the check automatically succeeds, and often includes a bonus for the roller.
    -   A natural 1 is a critical failure: the check automatically fails, and the attempt often causes an additional complication or challenge for the roller.

### Exploration Procedure

The general steps to take when exploring (dungeon, wilderness, etc.)

1. **Setup**: Referee describes the situation
2. **Marching Order**: Party determines general exploration process, including direction of travel and speed.
3. **Complication Check**: Referee rolls the complication die to see what effect it has.
4. **Actions / Responses / Complications**: Party declares actions, referee describes the results (and any complications).
5. **End Turn / Watch**: When the party has gone far enough or combat has completed, the (dungeon) turn or (wilderness) watch ends.

    - Dungeon: 240'
    - Wilderness: 6 miles

6. **Repeat**: Return to step 2 and repeat until the adventuring ends.

#### Complication Check

Roll 1d6, ignoring results of 4+ for the first 4 turns in a session (or since they last occurred).

1. **Encounter**: Wandering creature, social encounter, or some other random interaction.
2. **Signs / Portents**: Indications of possible encounter nearby - could be a clue, monster tracks, etc.
3. **Locality**: Some environmental or external event that affects the PCs - water rises, the assassin gets closer to the target, doors lock behind the party, etc.
4. **Exhaustion**: Take a rest turn (short rest) or (additional) -1 to all rolls until you do.
5. **Light Source**: Torches go out, lanterns go out every third time.
6. **No Complications**

#### Darkness

-   -4 to attack when unable to see
-   Candles light 10' radius
-   Torches / lanterns light 30' radius

#### Infravision

-   Can see heat tones, even in the dark.
-   Usually works to 60'.

#### Listening at Doors

Spend a minute listening at a door to have a base 1-in-6 chance of hearing a noise.

-   Referee makes this roll.

#### Opening Doors

-   Locked Doors can be picked or broken.
    -   Picking a lock takes 1d6 minutes.
-   Stuck Doors can be unstuck or broken.
-   Doors always break on a 1. Failure can affect stealth / surprise.

<div class="dividedTableWrapper">

|  STR  | Unstick | Break  |
| :---: | :-----: | :----: |
|  3-8  |   ---   | 1-in-6 |
| 9-12  | 2-in-6  | 1-in-6 |
| 13-15 | 3-in-6  | 2-in-6 |
| 16-17 | 4-in-6  | 3-in-6 |
|  18+  | 5-in-6  | 4-in-6 |

[Forcing Door Chances]

</div>

##### Exhaustion

-   Exhausted creatures attack and deal damage at -2, and get -2 to their AC.
-   Exhaustion can be cleared by resting for 30 minutes (3 turns).

#### Other Hazards

-   Fall damage is 1d6 / 10'.

#### Swimming

-   Creatures are assumed to be able to swim at 1/2 their normal movement speed.
    -   Unless the creature is just floating, a STR or CON check is required every turn (10 minutes).
        -   For creatures carrying heavy loads or wearing metal armor, this check is required very combat round (10 seconds).
        -   Failing this check results in a loss of 1 HP, and the check must be immediately attempted again.
        -   The third failure indicates the creature begins **drowning**``.

#### Drowning

-   Each combat round, a drowning creature must **Save vs Death** or take 1d8 drowning damage.
-   When a drowning creature is rescued, it becomes exhausted.
-   Once the exhaustion clears, the creature gains back any HP lost to drowning.

#### Urban Navigation

To navigate to a location in a busting city, make a Reaction Roll (2d6) + CHA mod + INT mod.

-   Modify roll in friendly, dangerous, or especially alien areas.
-   Navigation time includes time spent reading maps and getting directions, as well as any eating or rest stops needed along the way.
-   Roll random encounter checks each hour

<div class="dividedTableWrapper">

| Roll |  Result   |       Time Spent       |
| :--: | :-------: | :--------------------: |
|  2   |  Failure  |  Waste day searching   |
| 3-5  | Wandering | Arrive after 2d4 hours |
| 6-8  |  Success  | Arrive after 1d6 hours |
| 9-11 | Fortunate | Arrive after 1d4 hours |
| 12+  |  Direct   |  Arrive after 1 hour   |

[Urban Exploration Results]

</div>

#### Wilderness Exploration

-   Distances and non-magical ranges are tripled (yards rather than feet).
    -   Areas of breath weapons and spell effects are still measured in feet.

**Flight**

-   Unless stated otherwise, flight distance is double that of overland travel.
    -   Flight speed is not affected by terrain.
-   Winged beasts may be used as **mounts**, carrying riders or cargo based on the mount's HD:
    -   3 HD: May carry a creature 1/2 the size of a humanoid.
    -   6 HD: May carry a creature the size of a humanoid.
    -   12 HD: May carry a large creature (ex: horse)
    -   24 HD: May carry a huge animal (ex: elephant)

<!--

**Foraging**

-   May be performed while traveling at normal pace.
-   Party has 1-in-6 chance of foraging enough for 1d6 characters

**Hunting**

-   Takes a complete day (no travel or resting possible).
-   Party has 1-in-6 chance of encountering game.
    -   This is in addition to normal random encounter chances.

**Light**

A full moon (or fog, heavy rain, etc., during daytime) with a
clear sky will create an area of dim light. Otherwise, night
and very thick fog will create darkness. See the Dungeon
Adventures section for the effects of darkness.

**Losing Direction**

-   At the start of each day, referee should roll to determine if group loses direction.
-   Chance of losing direction depends on terrain being traversed:
    -   Grasslands, plains, clear: 1-in-6
    -   Hills, mountains, woods, barren areas: 2-in-6
    -   Swamp, jungle, desert: 3-in-6

-->

**Overland Travel**

-   The distance in miles that a character can travel overland in a day (16 hours) under normal conditions (and clear terrain) can be determined by multiplying their base movement rate by .6 (or 3/5).

    -   10' / round => 6 miles / day
    -   20' / round => 12 miles / day
    -   30' / round => 18 miles / day
    -   40' / round = 24 miles / day

-   Some terrain affects overland speed while traveling through it:

    -   Maintain roads: Increase speed by 50%.
    -   Hilly, wooded, or desert terrain: Decrease speed by 33%.
    -   Swampy, mountainous, or jungle terrain: Decrease speed by 50%.

-   Characters engaged in a forced march can increase their travel speed by 50%, but must rest for a full day or suffer exhaustion (-1 to all rolls).

-   Characters must rest 1 day for every 6 days traveling or suffer exhaustion (-1 to all rolls, cumulative for each additional day without rest).

**Sight**

Characters can usually see 3 miles around (in clear terrain).

-   Range of sight may vary based on terrain (ex: less in wooded area, more on an overlook).

### Encounter Procedure

1. **Check Stealth**: Referee rolls for stealth, if applicable.

    - Each side that's being relatively stealthy (quiet, douses torches, etc.) has a base 2-in-6 chance of not being spotted.
    - Parties carrying an active light source typically can not have stealth.
    - If only one side has stealth, they may usually make a free attack (or can pass unnoticed).
    - If all sides have stealth, they miss each other.

2. **Determine Distance**: Referee determines how far away the characters are from the encounter.

    - Often determined by the nature of the encounter itself, but may be determined randomly:
        - Dungeon: 2d6 x 10'
        - Wilderness: 4d6 x 10 yards (or 1d4 x 10 yards if either side is surprised).

3. **Roll Initiative**: Each side that has stealth rolls 1d20, highest roll moves first.
4. **Choose Actions**: Each side decides how they will respond in initiative order, and the encounter proceeds.
    - Players decide how their characters will act.
    - Creature actions are often determined by the nature of the encounter itself, but may be determined randomly.
        - If creature / NPC reaction isn't obvious, roll 2d6 (+ CHA modifier, if someone tries to communicate).

<div class="dividedTableWrapper">

| 2d6 |   Result    |
| :-: | :---------: |
| 2-  |   Attack!   |
|  3  |   Hateful   |
|  4  |    Leery    |
|  5  |    Rude     |
|  6  |    Aloof    |
|  7  |  Uncertain  |
|  8  |  Confused   |
|  9  | Indifferent |
| 10  |   Cordial   |
| 11  |   Amiable   |
| 12+ |  Friendly!  |

[Reaction Table]

</div>

<div class="dividedTableWrapper">

|  CHA  | Mod |
| :---: | :-: |
|   3   | -3  |
|  4-5  | -2  |
|  6-8  | -1  |
| 9-12  | +0  |
| 13-15 | +1  |
| 16-17 | +2  |
|  18+  | +3  |

[Charisma Modifier]

</div>

5. **End Turn**: Once the encounter has played out, the turn ends.

-   Each encounter is assumed to take at least one full turn to complete.
    -   This includes time to regroup, bind wounds, clean weapons, rest, etc.

#### Typical Actions

While any action is possible, the following actions are the most common:

-   **Combat**: If a side attacks, casts a spell, or makes a tactical movement, [combat](./combat.html) begins.
-   **Evasion**: If a side decides to flee, another side may decide to pursue.
-   **Talk**: One side may attempt to communicate with the other(s).

#### Evasion

Any side that wishes to avoid an encounter may attempt to flee.

-   Only possible before combat begins.
-   Each opposing side declares whether or not they want to pursue.
    -   Players decide freely if they wish to pursue fleeing creatures.
    -   Referee decides whether creatures pursue fleeing PCs (based on circumstances or roll).
-   If all opposing sides decide not to pursue, the evasion attempt automatically succeeds and the encounter is avoided.
-   If an opposing side decides to pursue, the chance of evading depends on the surrounding environment.

### Advancement

As the adventures continue, treasure is acquired and creatures are vanquished, all adding to the PCs XP total.

-   Each standard coin worth of treasure gained is worth 1 XP, and each creature has an XP value awarded for beating them (one way or another).
-   The total XP are then divided amongst the PCs and any hirelings they have (at 1/2 share per hireling).
    -   Players running multiple characters gets a full share for their first PC and a half-share for the second, although they choose how to distribute the points.
-   Referees may increase the derived value arbitrarily.
-   Once a PC acquires enough XP, they go up to the next level in their class.

#### Upon Gaining a Level

When a PC increases their level, the following actions may be performed:

-   Roll a hit die (based on the PC's class), and add it to their maximum hit points.
    -   1s and 2s may be re-rolled.
    -   Alternatively, roll the next die step down and add 2.
-   Their player may pick one of the PC's abilities, and roll 3d6.
    -   If the resulting roll is higher than the ability score, increase the score by 1.
-   Check the PC's [class](/classes/index.html) and [race](/races/index.html) to see if any new abilities are gained.

### Encumbrance

Characters can carry a number of "Important Items", based on their Strength (STR).

-   Items can be carried **At Ready** or **Packed**.
    -   "At Ready" items may be grabbed and used without delay.
    -   Packing or unpacking items takes 1 turn.
-   Characters can carry a number of at-ready items up to their Strength (STR), to a minimum of 7.
    -   Additionally, characters may carry a number of packed items up to their Strength (STR), to a minimum of 7.
-   Leather armor (with or without studs) counts as 1 item, chain mail and half plate each count as 2 items, and full plate counts as 3 items.
-   2-handed weapons count as 2 items.
-   100 coins or gems count as 1 item.
-   Carrying more ready or packed items than allowed can be done, but movement is halved (or worse).
    -   Carrying more than twice the allowed number of ready or packed items reduces movement to 0.

### Health, Damage and Dying

The state of a character's health is determined by their number of hit points (HP).

-   Starting HP is usually determined by class and level.
    -   The type of Hit Dice to throw is determined by class
    -   The number of Hit Dice to throw is determined by level.
    -   Re-roll any 1s or 2s.
    -   Modify the rolled value of each die by CON as below:

<div class="dividedTableWrapper">

|  CON  | Mod |
| :---: | :-: |
|   3   | -3  |
|  4-5  | -2  |
|  6-8  | -1  |
| 9-12  | +0  |
| 13-15 | +1  |
| 16-17 | +2  |
|  18+  | +3  |

[Constitution Modifier]

</div>

-   When damage is taken, HP is lost.

#### Dying

-   Monsters and NPCs usually die at 0 HP.
-   PCs at 0 HP (or lower) make a **Saving Throw vs Death** at the end of each round of combat.
    -   On success, stabilize at 1 HP (no need to continue saving vs death), but can't fight and can only move 1/2 speed until treated or healed.
    -   On fail, lose 1 HP to blood loss and try again next round.
    -   At -(level) HP (or lower), save or die.
-   PCs should never die from a single bad roll, but two bad rolls is enough.

#### Healing

-   After each long rest (8+ hours of sleep), regain 1 _hit die (HD)_ worth of HP.
-   Once per day, take a short rest (10 minutes) and eat a ration to regain 1 HD worth of HP.
-   Certain potions of healing can also be used:
    -   Drinking a healing potion restores up to 1d6+1 HP.
    -   Imbibing a potion of greater healing restores up to 2d6+2 HP.
    -   Quaffing a potion of supreme healing restores up to 3d8+3 HP.

### Knowledge

**Identifying (Magic) Items**: Spellcasters get INT check.

**Medical Treatment**: INT check, success stabilizes dying characters and restores their ability to move and fight.

-   Can't be used on oneself.

### Languages

-   Anyone who speaks a language can understand other related lanuages (ex: dialects) with a successful INT check.
-   Some orders and guilds (especially those that engage in illegal / immoral acts) may teach their members secret or otherwise coded language.
-   The following lists of languages are not all-inclusive.

#### Alignment Languages

Assumed to shared by all (intelligent) members of a given alignment.

-   **Chaotic**: Alignment language of chaos.
-   **Lawful**: Alignment language of law.
-   **Neutral**: Alignment language of neutrality.

#### Class Languages

Most class languages are secret, known only to members of their class, and often include coded terms and/or physical motions (hand waves, knocks, etc.).

-   **Assassin's Cant**: Secret (and coded) language known to all thieves.
    -   Dialects are based on different guilds.
-   **Corsair's Cant**: Secret (and coded) language spoken by all Corsairs.
    -   Dialects are based on different ship / locations.
-   **Druidic**: Secret language spoken by all Druids.
-   **Thieves' Cant**: Secret (and coded) language known to all thieves.
    -   Dialects are based on different guilds.

#### Racial Languages

-   **Aerian**: Native language of air elementals, dialect of elemental.
-   **Angelic**: Native language of angels (law elements), dialect of both lawful and elemental.
-   **Aquon**: Native language of water elementals, dialect of elemental.
-   **Demonic**: Native language of demons (chaos elements), dialect of both chaotic and elemental.
-   **Doppleganger**: Native language of dopplegangers.
-   **Draconic**: Native language of most intelligent reptilian races (kobolds, troglodytes, lizardfolk, dragons, dracokin, etc.).
-   **Duncommon**: Native language of those that dwell deep underground and other dark places (Drow, Medusa, etc.).
-   **Dwarfish**: Native language of dwarves.
-   **Elemental**: Spoken by all elementals, each subtype has their own dialect.
-   **Elvish**: Native language of elves, dialect of faerie.
-   **Faerie**: Native language of the fae, usually divided into 2 dialects:
    -   **High Faerie** Spoken in the ruling courts of the Faewolde.
    -   **Low Faerie**: Spoken everywhere else in the Faewolde.
-   **Farspeak**: Language of the far realms.
-   **Gargoyle**: Native language of gargoyles.
-   **Giant**: Native language of giants.
-   **Goblinoid**: Native language of most intelligent goblinoid races (boggarts, bugbears, goblins, hobgoblins, etc.)
-   **Gnollish**: Native language of gnolls.
-   **Gnomish**: Native language of gnomes.
-   **Greyok**: Native language of several intelligent mammalian animalkin races (Elekin, Hippokin, Rhinokin, Taurokin).
-   **Halfling**: Native language of halflings.
-   **Orcish**: Native language of ogres and orcs.
-   **Pyrean**: Native language of fire elementals, dialect of elemental.
-   **Strallan**: Native language of the Stral and official language of the Stral Empire.
-   **Terrun**: Native language of earth elementals, dialect of elemental.

<div class="dividedTableWrapper">

|  INT  | Spoken Languages | Read? |
| :---: | :--------------: | :---: |
|   3   | Native (broken)  |  No   |
|  4-5  |      Native      |  No   |
|  6-8  |      Native      | Basic |
| 9-12  |      Native      |  Yes  |
| 13-15 |    Native + 1    |  Yes  |
| 16-17 |    Native + 2    |  Yes  |
|  18+  |    Native + 3    |  Yes  |

[Languages Known]

</div>

### Perception Checks

Generally, perception can be checked by rolling highest of INT or WIS.

### Size

A creature's size is usually defined by one of the following categories based on its height and/or weight:

<div class="dividedTableWrapper">

|    Size    | Max Height |  Max Weight  | Control Radius |
| :--------: | :--------: | :----------: | :------------: |
| Diminutive |     1'     |     1 lb     |       1'       |
|    Tiny    |     2'     |    8 lbs     |      2.5'      |
|   Small    |     4'     |    60 lbs    |       5'       |
|   Medium   |     8'     |   500 lbs    |       5'       |
|   Large    |    16'     |   4000 lbs   |      10'       |
|    Huge    |    32'     |  32,000 lbs  |      15'       |
| Gargantuan |    64'     | 250,000 lbs  |      20'       |
|  Colossal  |    65'+    | 250,001+ lbs |      30'       |

[Creature Sizes]

</div>

### Time

Time is often represented at different scales:

-   A combat round is 10 seconds long.
-   An exploration turn takes 10 minutes.
-   A watch takes 4 hours.
-   A long rest takes 8 hours.

<!--
### Usage Die

Some equipment (including many magic items) have limited uses, tracked via a **Usage Die**.

-   The item description will indicate the starting die type.
-   After each use, roll the current die, and on a 1-2, the die drops one step (d20 -> d12 -> d10 -> d8 -> d6 -> d4 -> 1) as uses are consumed.
    -   After dropping a die step from a d4, the magic item has only 1 use remaining.
-   When no more uses are left, the item becomes inert.
-   At the referee's discretion, it may be possible to recharge some magic items, increasing the usage die via complex magic rituals.
-->

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