traps

This post was originally posted in 2018. I’ve re-posted it with updated artwork, but haven’t changed anything about the post itself. I’m still pretty happy with this!

While you’re here – it’s my birthday this week, so all of my games on itch.io are currently on sale. Go check it out!

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If you follow me on Twitter you’ll have seen that I’ve been working my way through back issues of Dragon Magazine, beginning at issue #1. As well as being a fascinating glimpse into the history and development of this hobby that I love so much, I’ve also been finding some useful things among those pages – and some things that could be useful, but fall a little short of the mark.

One of those things crops up in Issue #15 in the form of an article entitled “PITS” by Richard Morenoff, which presents “A set of charts to help the dungeon master when player characters or monsters fall into a pit”.

What follows are a series of random roll tables to help determine what might actually be in the pit. I got unreasonably excited by this when I saw the article, but unfortunately the tables themselves aren’t much use if we want to generate interesting results. 60% of the time the pit is simply an empty pit; to my mind, the point of rolling on a table like this is when you want something other than an empty pit. The rest of the results are fairly typical of early D&D, with most of them being some variant of a monster/random NPC/spellcaster who is tied or chained down in the pit, or else generating a pit of snakes or random oozes. One of the results even directs DMs to roll on the D&D monster matrix to generate a result, requiring you to turn to another book to finish generating your pit.

I think we can do better than that. The philosophy of dungeon design has changed in the intervening 40 years since this set of tables was published, so we need something that works with the modern game. I’d also like to preserve some of the strangeness of early games, too. My main goal, though, is to provide you with something quick and easy to use that a) doesn’t result in empty pits (and, thus, wasted time while rolling on the tables) and b) doesn’t require you to turn to another table somewhere else and roll on that (although you will need to consult the Monster Manual if you roll for any creatures).

A quick word to the wise; this table is very much in the vein of “save or suck”, which may not gell well with everyone’s preferred style of play. Be aware that using this table is guaranteed to ruin the day of at least one of your players.

Here’s what I’ve come up with.

PERILOUS PITS

Random pits for Fifth Edition

Using these tables is easy. Beginning at Table 1 – Concealment roll 1d100 and note the result, working through the tables in numerical order. Some categories contain sub-tables; entries on the main tables will direct you to roll on these depending on the result of your roll on that category’s main table. Once you have rolled on any sub-tables required for that category, move on.

Concealment

In all cases where a pit is not immediately visible, there is a 50% chance that there is visible evidence of dungeon creatures avoiding the pit. Spotting these tracks requires a passive Perception of 14 or higher.

Table 1: Concealment
1d100	Concealment	Passive Perception DC to spot
01-20	Open; immediately visible.	–
21-40	Concealed with tarp/cloth/a net	10
41-60	Concealed with wooden boards/a false floor	15
61-80	Concealed with a trap door. (50% chance the trap door closes and locks after the pit is triggered.)	18
81-100	Concealed with an illusion	20 (or spellcaster’s Save DC, if known)

The Basics

Determine the size of the opening and the depth of the pit by rolling on Table 2a: Opening and Table 2b: Depth. Then roll on Table 3a: Hazards, generating Additional Hazards and Creatures if necessary.

Table 2a: Opening
1d100	Opening
1-15	5’ square
16-30	5’ diameter circle
31-45	10’ square
46-60	10’ diameter circle
61-70	15’ diameter circle
71-80	Rectangular; 5’ x 10’
81-90	Rectangular; 5’ x 15’
91-100	Rectangular; 10’ x 15’

 

Table 2b: Depth
1d100	Depth	Base Falling Damage
1-20	10’	1d6
21-35	15’	1d6
36-50	20’	2d6
51-65	30’	3d6
66-75	40’	4d6
76-85	50’	5d6
86-95	60’	6d6
96-100	Bottomless. Roll for Hazards as normal, but do not roll for Special Features.

 

Table 3a: Hazards
1d100	Hazard	Effect
01-15	Spiked floor	11 (2d10) piercing damage plus base falling damage
16-25	Creature	Roll on Table 3c: Creatures
26-35	Pool of acid 10’ deep (or that fills the pit, if pit is less than 10’ deep)	5 (1d10) acid damage on entering the acid, and at the end of each turn spent in the acid
36-45	Pool of tar 15’ deep (or that fills the pit if pit is less than 15’ deep)	Creatures in the tar must succeed on a DC 15 Athletics (Strength) check to keep themselves afloat, repeating this save at the beginning of each turn spent in the tar. The speed of creatures in tar is reduced to 5’. Creatures failing the save sink and begin to drown (see drowning rules). Tar ignites if brought into contact with an open flame, dealing 11 (2d10) fire damage each round to any creatures in the tar.
46-55	Spiked floor as above, and roll for Additional Hazards
56-65	Creature as above, and roll for Additional Hazards
66-75	Acid as above, and roll for Additional Hazards
76-85	Tar as above, and roll for Additional Hazards
86-95	Quicksand	Functions as tar, but DC is 18. Minimum depth 10’; if the pit is deeper than this, quicksand fills it to within 5’ of the opening.
96-100	Sphere of Annihilation at the base of the pit	If pit is wider than 5’, DC 13 Dexterity saving throw to avoid the sphere. Otherwise, falling creatures make contact with it. See sphere of annihilation, see DMG p. 201. GM decides if the sphere is already under the control of another creature.

Additional Hazards

First roll to determine how many additional hazards are present. Then roll that many times on the Additional Hazards table. When rolling for multiple additional hazards, reroll duplicates.

Table 3b: # of Additional Hazards
1d100	# of times to roll on Table 3c
01-50	1
51-80	2
81-90	3
91-100	4

 

Table 3c: Additional Hazards
1d100	Hazard	Effect/Notes
1-15	Greased/oiled sides	Attempts to climb the sides of the pit are at Disadvantage
16-30	Spiked walls	Additional 3 (1d6) piercing damage per 10’ fallen
31-45	Spinning blades at base of pit*	Blades deal 16 (3d10) slashing damage to creatures at the bottom of the pit, and an additional 16 (3d10) slashing damage at the beginning of each subsequent turn. Blades can be disabled withsuccessful  a DC 15 Dexterity check using thieves’ tools.
46-55	Spinning blades on walls	Additional 16 (3d10) slashing damage per 10’ fallen. Climbing the pit requires a successful DC 20 Dexterity (Acrobatics) check to avoid the blades. Creatures who fail this save take 16 (3d10) slashing damage and fall back to the bottom of the pit. Blades can be disabled with a successful DC 15 Dexterity check using thieves’ tools.
56-65	Rotting bodies at the bottom of the pit	Creatures falling to the bottom of the pit must succeed on a DC 13 Constitution saving throw or be infected with Sewer Plague (see DMG, p. 257)
66-75	Contact poison on walls	Creatures attempting to climb the walls must succeed on a DC 18 Constitution saving throw or take 11 (2d10) poison damage and be poisoned.
76-85	Greased/oiled sides, and roll for Special Features
86-90	Spiked walls, and roll for Special Features
91-95	Contact poison on walls, and roll for Special Features
96-100	Roll again on this table, and roll for Special Features.	If second roll also results in Special Features, roll twice on that table.
* Items marked with an asterisk do not appear in bottomless pits. Ignore these hazards if rolled. Do not roll again to replace them.

 

Table 3d – Creatures

Table 3d: Creatures
1d100	Creatures
01-15	1d12 constrictor snakes
16-30	Gelatinous cube
31-45	Black pudding
46-60	1d4 giant scorpions
61-70	1d6 skeletons
71-80	Carrion crawler
81-90	Chest mimic
91-100	Troll; 50% chance it is chained to an iron ring in the ground.

 

Special Features

Table 4a: Special Features
1d100	Special Feature
01-15	Pit widens at the bottom and is a monster’s lair. The only way out is through the pit. Choose a suitable monster according to your dungeon’s needs.
16-30	Pit can be bypassed by secret doors concealed on the surface at both sides of the pit.
31-45	Secret door at the base of the pit reveals a staircase back to the surface. DC 15 to locate. 50% chance the door is locked.
46-60	Secret door at the base of the pit reveals a staircase back to the surface. DC 15 to locate. Door is barred from the other side.
61-75	Pit is located in the ceiling, and it and the space directly beneath it are subject to a Reverse Gravity spell. All other features remain the same.
76-90	Top 5’ of the pit is a sliding block of stone that slams shut after a creature reaches the bottom of the pit, separating the creature from her companions as though she was on another level of the dungeon. Creatures located in the top 5’ of the pit when the block is triggered suffer 44 (8d10) bludgeoning damage, with a 50% chance of being pinned in place by the block and a 50% chance of falling into the pit.
91-100	Base of the pit is a teleportation portal. Roll on 4b: Teleportation Destination to determine where this leads.

Teleportation Destinations

Table 4b: Teleportation Destinations
1d100	Teleportation Destination
01-20	Ceiling directly above the pit.
21-40	Random point in the dungeon, as determined by the GM.
41-60	Entrance to the dungeon.
61-80	Random point within 100 miles (roll 1d4 to determine cardinal direction and 1d1000 to determine height above sea level in feet).
81-100	Random point on a random plane of existence, as determined by the GM.

 

 

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Image Credit: Rustam rescues Bihzan from the pit, watched by Manizeh. Gouache painting by an Indian artist, ca. 1800. Credit: Wellcome Collection. Attribution 4.0 International (CC BY 4.0)