Drawing inspiration from…
Whitebox: FMAG by Charlie Mason
Delving Deeper by Simon J. Bull
Swords & Wizardry by Matthew J. Finch
Original Edition Delta by Daniel Collins
Searchers of the Unknown by Nicolas Dessaux
Necropraxis by Brendan S.
Coins and Scrolls by Skerples
E. Gary Gygax
Dave Arneson

With thanks to my wife and editor, Shelby.

An Underwater Owlbear game.

Character Creation

Basic Rules

If coming from other old-school games, these are the assumptions used for a few important rules:

• HD are d6 for all character classes and all monsters.
• To-hit bonus equal to HD for all classes and all monsters.
• Ascending AC with unarmored AC = 10.
• Roll-over saving throws.
• Weapon damage is d6 unless otherwise noted.

When you have advantage on a roll, roll two dice instead of one and take the better result. When you have disadvantage on a roll, roll two dice instead of one and take the worse result.

Experience and Advancement

Pick a class (fighter or mage). You start at 1st level with 0 experience points (XP). You gain 1 XP for every coin that you spend on carousing, partying, donating, gambling, or other pursuits without material reward. Slaying monsters may award XP as well, but this is significantly more dangerous and less rewarding than stealing treasure.

When you gain a level, roll all of your hit dice (HD). They are d6. If the sum of dice rolled is greater than your current maximum HP, the sum becomes your new maximum HP. If it is equal to or less than your current HP, gain +1 HP instead. HD for player characters and monsters are always d6.

Fighter

You start with d6 HP (minimum 3 HP) and 3d6x10 coins. Fighters can use all weapons and any armor, shield, or helm. When they reach 9th level, they become a Lord (or Lady) and can build a stronghold to attract subjects.

Cleave
Upon slaying an enemy, a fighter may immediately make an additional attack against an enemy within reach.

Mage

You start with d6 HP and 3d6x10 coins. Mages may use knives, clubs, and staves, and may not use armor, shields, or helms. When they reach 9th level, they become a Wizard (or Witch), and can build a tower (or hut) to train apprentices.

Spellcasting
Mages may memorize and cast a number of spells per day of a maximum spell level as indicated by the table below. Mages start with three 1st level spells written in their grimoire, and can transcribe more into their grimoire from scrolls.

Equipment

Encumbrance and Movement

A stone (st) is an archaic unit of measure equal to about 4 pounds. It is used to simplify encumbrance and bookkeeping. 300 coins weigh 1 stone. Consult the table below for encumbrance limits for various creatures. When encumbered, movement speed is halved. When mounted, movement speed in combat is doubled. Note that a rider weighs 40 stone. A larger unit of measure is the hundredweight (cwt) used for measurements of bulk cargo. One hundredweight weighs 20 stone.

Weapons, Armor, and Equipment

A “2H” indicates that the weapon requires two hands to wield.
A “Th” indicates that the weapon may be thrown

Hand Axes deal triple (3x) damage on a critical hit.

Battle Axes deal triple (3x) damage on a critical hit, and grant +1 to initiative rolls.

Bows require arrows – a quiver of which is depleted after combat on a roll of 6+ on a d6.

Knives deal d6 damage against surprised enemies.

Pikes deal 2d6 damage against charging enemies, and grant +1 to initiative rolls.

Slings can use rocks and pebbles as ammunition.

Staves grant +1 AC if the wielder did not attack last turn.

Spears deal 2d6 damage against charging enemies.

Swords reroll damage roll results of 1, due to their keen edge (subsequent results of 1 beyond the first are not rerolled).

Torches can set flammable targets alight, or deal d6 damage against enemies vulnerable to fire.

Plate armor cannot be purchased from most armorers. It is a rare and valuable artifact.

Shields can be sundered to negate all damage from a hit.

Helms can be sundered to turn a critical hit into a regular hit (only deals 1x damage, rather than 2x).

Bedrolls allow enough rest in the wilderness to regain d3 HP per night.

Tents give enough shelter to heal d6 HP per night in the wilderness.

Candles provide enough light for two (2) people.

Torches prove enough light for four (4) people.

Tinderboxes are used to light fires. In most situations, this is done easily. However in stressful or threatening situations, lighting a fire requires a roll of 5+ on a d6.

Backpacks can hold 10 stone, which is an unencumbering load.

Crosses will repel undead when presented, forcing them to make a successful saving throw to attack the bearer.

Crowbars grant a +1 bonus to rolls to open doors.

Grimoire have 100 pages. A scribed spell will take up a number of pages equal to its spell level.

Pickaxes allow the user to move 25 ft³ of rock every 4 hours.

Sacks hold either 8 stone (large sacks) or 4 stone (small stacks).

Shovels allow the user to move 25 ft³ of dirt every 2 hours.

Spikes can be used to wedge doors open or shut. Overcoming a spike requires a successful open doors check.

Carts double (2x) the carrying capacity of the user.

Wagons quadruple (4x) the carrying capacity of the user.

Mules have a morale score of 7.

Horses have a morale score of 6.

Warhorses have a morale score of 9.

Canoe, small – weighs 6st, carries 2 men and 12 cwt of cargo.

Canoe, medium – weighs 12st, carries 6 men and 30 cwt of cargo.

Voyager canoe – weighs 24st, carries 12 men and 60 cwt of cargo.

Hirelings

It costs 100c to place an advertisement in a settlement for hirelings. The advertisement lasts for 1 week and provides d6+1 prospects for hiring. Hirelings are not brave or foolhardy enough to enter dungeons, but can be used for logistical support to and from dungeons and for guarding camp.

Horse archers may act in both the move phase and the missile phase of combat.

Combat

Reactions

When encountering a wandering monster or other entity, and their disposition is unknown, roll 2d6 to determine their reaction.

Morale

When a side takes 50% casualties, make a morale check to see if they break. Roll 2d6; a result greater than the morale score means that the side routs and flees the field. Undead are always hostile, never check morale, and normally cannot be reasoned with (intelligent undead such as liches are an exception). Morale is usually based on the combatants experience level, per the table below.

Surprise

To determine surprise, roll a d6 for each side that is unaware of their enemies. On a 5+, they are surprised. If a side is surprised, they are unable to act in the first round of combat.

Common situations where players may surprise monsters:

• Bursting through a door on the first try.
• Entering a room by picking the a locked door.
• A thief successfully hides in shadows or moves silently (only thief has initiative, the rest of the party must roll as normal).

Common situations where monsters may surprise players:

• The party has no light sources.
• The party enters a room after an unsuccessful attempt to burst open the door.

Initiative

To determine initiative within the combat round, roll a d6 at the start of combat. On a 4+, players have the initiative. On a 3 or less, the monsters have the initiative. Combatants take their actions in the following phases, with the side having the initiative acting first in each phase:

1. Magic, cast
   • Spellcasters declare what spell (if any) they will cast that turn, and begin to cast it.
     
2. Move or Missile
   • Combatants move or fire a missile.
   • Some special units such as horse archers may move and fire a missile.
     
3. Melee
   • Combatants make attacks in melee
     
4. Magic, effect
   • Spells cast this round take effect.
   • Spells cast by the side with initiative take effect first.

Attacks and Damage

Roll a d20 and add your to-hit bonus. A character or monster’s to-hit bonus is equal to their HD. Results that meet or exceed the target’s armor class (AC) deal your weapon’s damage to the target. The target reduces their HP by that much. Attack rolls of 20 are critical hits that deal double damage to the target.

Charge

A combatant may charge an enemy by moving from outside of melee range to within melee range of an enemy in the movement phase. The charging combatant gains advantage on their next attack against the charged enemy.

Withdraw

When a combatant within melee range of an enemy moves out of melee range, the enemy may immediately make a melee attack against the combatant. This can be avoided if the combatant only makes a half move.

Combat Maneuvers

A combatant can choose to trip, disarm, blind, or otherwise perform a dirty trick on his opponent. He makes an attack and damage roll as normal. If he hits, his opponent can choose to take damage as normal, or suffer the effects of the combat manuever.

Saving Throws

Some effects require characters to make saving throws. To do so, roll a d20 and compare the result to your character’s saving throw score on their character sheet. A result equal to or greater than the saving throw score is a success.

Death and Healing

When a combatant reaches 0 HP, they must make a saving throw. On a failure, they die. On a success, they are merely grievously wounded.

Characters may bind their wounds after combat to restore 1 HP of damage sustained in that fight. Resting in camp for a night restores some HP (depending on the comfort of your camp). Resting in a town or similar safe location for a night restores all HP. The grievously wounded require a week’s rest in a town or similar safe location to restore all HP.

Dungeon Delving

Turns

One turn of dungeon exploration takes about ten (10) minutes, and generally allows the party to take one action, such as:

• Move to the next room
• Open a stuck or locked door
• Search the current room
• Rest and bind wounds
• Interact with a feature of the room, such as a trap

Doors

All doors are stuck and must be burst open by force with a 5+ on a d6. A failed attempt makes surprising whatever is behind the door impossible. Characters can listen at doors and attempt to hear if the room is occupied on a roll of 5+ on a d6. Note that the undead make no sound.

Secret doors require the room they are in to be searched completely (takes one turn, sometimes more for larger rooms) Some doors are locked, and require a key or a thief to pick the lock to open.

Doors will open freely for monsters unless wedged shut with iron spikes. When wedged shut, monsters must attempt to burst the door open as above, possibly giving the party time to hear them coming. Doors can also be wedged open with spikes, to ensure the party a clear path of escape.

Traps

Traps are activated on a roll of 5+ on a d6. They can be detected by spending a turn searching the area. Thieves can attempt to disarm traps; but be careful, as a failure will trigger the trap. If you don’t want to risk this, find a clever way to bypass the trap.

Encounters

Every turn of exploration, or every time the party rests or makes excessive noise, roll a d6 on the event table below. Choose the result from the appropriate column depending on whether all, some, or none of the characters in the party have light.

W = Wandering monster encounter. Roll for an encounter on the appropriate encounter table.
O = Omen. Signs of a wandering monster are encountered.
L = Light sources depleted. All currently lit light sources are depleted. New light sources are automatically lit as a free action (unless in combat, see tinderbox rules).

Chases

Monsters may chase fleeing characters. Each turn of the chase, roll a d6. Consult the table below to determine what happens. Note that closed or locked doors may be in the way of the fleeing party. These must be dealt with as normal - failure indicates they are stymied by the obstacle long enough for the pursuing monster to catch them.

C = Caught. The monster catches the fleeing party, and engages them in combat.
M = Moves. The chase continues into the next room of the dungeon.
E = Escape. The party successfully evades the monster.

Food will distract unintelligent monsters from the chase, by dropping 1 days ration per monster HD. Treasure will distract intelligent monsters from the chase, by dropping 100c worth of treasure or coins per monster HD. Passing through a secret door will always evade a pursuer.

Appendix

Monsters, Treasure, and Spells

It is suggested to reference one of the following resources for monster lists, treasure tables, and spell lists:

• White Box: Fantastic Medieval Adventure Game by Charles Mason
• Delving Deeper Reference Rules Hypertext by Simon J. Bull
  • Monsters
  • Treasure
  • Spells

Monsters are able to see in complete darkness. When converting monsters from other publications, their saving throw and to-hit bonus should be based on the number of HD. A monster’s saving throw is found by subtracting it’s HD from 19 (for example, a 2 HD monster has a saving throw of 17). A monster has a to-hit bonus equal to its HD. HD should be converted to d6. Monsters typically deal d6 damage per attack, though particularly dangerous monsters might deal multiple d6 per attack.

Thief

Thieves can use clubs, knives, staves, and bows, and wear padded armor or mail, but cannot use shields or helms. When they reach 9th level, they become a Master Thief, and can set up a hideout to attract fellow criminals.

Thievery
Thieves may use their thievery skill to perform the following feats of stealth and skulduggery:

• Hear noises through doors or across rooms
• Pick locks or disable traps
• Move silently or hide in shadows
• Pick pockets

To succeed, they must roll the indicated number or higher with a d6. However, thieves take a -1 penalty to these attempts when wearing mail armor.

Backstab
Thieves deal double damage against surprised opponents.

Open Game License

OPEN GAME LICENSE Version 1.0a

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15. COPYRIGHT NOTICE

Open Game License v 1.0a Copyright 2000, Wizards of the Coast, Inc.

System Reference Document Copyright 2000–2003, Wizards of the Coast, Inc.; Authors Jonathan Tweet, Monte Cook, Skip Williams, Rich Baker, Andy Collins, David Noonan, Rich Redman, Bruce R. Cordell, based on original material by E. Gary Gygax and Dave Arneson.

Delving Deeper Reference Rules Compendium v4a, Copyright 2014, Simon J. Bull

Delving Deeper Reference Rules Hypertext, Copyright 2014, Simon J. Bull

White Box: Fantastic Medieval Adventure Game, Copyright 2016, Charles Mason

Barrows and Basilisks, Copyright 2021, Tyler Farrington

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