D&D Companion: The Adventure

"Part 4: The Adventure" in Moldvay Basic describes encumbrance, (new equipment is introduced in Cook/Marsh Expert, for which values for encumbrance are not provided).

A Companion supplement should include the encumbrance of new ("optional") equipment, such as new types of armor, the heavy crossbow, bastard sword, and other weapons.

Molday Basic covers the dungeon environment, while Cook/Marsh Expert describes the wilderness.  The Companion Supplement should cover new environments.

Illustration by Rebecca Guay

Underwater Adventures:

Underwater adventures were first covered in the Blackmoor supplement.  Module X7 "The War Rafts of Kron" (1984) by Bruce Nesmith provided several new rules for underwater adventures, which could be used as the basis for material in the Companion supplement.*

*see also PC3 "The Sea People" (1990) by Jim Bambra

Drowning

If a character cannot breathe, he suffocates and dies.  A character can hold his breath for three rounds if he is active.  If he takes no actions, the character can hold his breath for six rounds.  After that he begins to drown and in three more rounds is dead.  However, his body has suffered no points of damage.

Underwater Movement

Module X7 has an Underwater Movement Table showing the speed characters may move underwater.  The table has a Sink/Rise column which shows how fast a character sinks or rises underwater.  If a fighter with plate mail, a sword, and a shield falls into the ocean, he sinks 20 feet per round because he has 660 coin weight of encumbrance.  If he removes his armor and shield, he rises 10 feet per round.

Underwater Movement Table, from X7 "The War Rafts of Kron" (1984) by Bruce Nesmith

If a character is swimming, add or subtract the swimming speed from the sinking or rising speed.  For example, a person carrying 350 coin weight of encumbrance sinks 10 feet per round if he does nothing.  If he swims, he can either stay even by swimming upward or swim downward 20 feet per round.  If he swims horizontally he will sink 10 feet per round while moving 10 feet per round.

Light

Seeing underwater is more difficult than seeing above water.  Just under the surface of the water a person can see 500 feet with natural lighting.  For every 100 feet below the surface, the range of vision is reduced 50 feet.  A person 1,000 feet or more under water is in complete darkness.

A light or beacon can be seen only half as far away as normal and can illuminate an area only half as large as normal, regardless of the depth of the water, (ie. a light spell would illuminate only a 15' diameter area; a continual light spell a 30' diameter area).

Sound

Noises travel farther underwater than in the air.  All sounds should be much louder and a little distorted if characters are underwater.  Navigators quite often use sound instead of light for navigation underwater.

Writing Underwater

Normal ink smears underwater.  Normal documents and writings become indecipherable in two turns.  This includes maps, but not magical writings.  If the party wishes to map the areas they investigate underwater, they must use a different system of mapping.

Extraplanar Adventures:

For information concerning adventures on the ethereal or astral planes, see Part 9: Special Adventures

Experience Points:

An expanded table for giving experience points should also be included.