Return to Undermountain
Room 5: Gate-Fall Hall (EL 6)
By Matthew Sernett

Room Summary

Creatures: (12) Nine 1st-level kobold warriors, two 2nd-level kobold fighters, and one 4th-level kobold fighter.
Traps: (1) Two falling portcullises brought down by pulling a lever.
Terrain: Normal, but falling portcullises can block movement.
Lighting Conditions: Darkness and a darkness curtain. Darkness: Be sure to keep track of sighting distances between foes in the long halls. Darkness Curtain: This opaque curtain of darkness completely blocks sight (even darkvision), but it is otherwise harmless; note the curtain's location on the map.
Magic: None except treasure.
Detectable Alignments: None or faint evil. The kobolds detect as faint evil, but they should be out of range at the beginning of the encounter.
Secrets: (2) There is a secret door in the room, and a hidden lever drops and raises two portcullises.
Treasure: The kobold's equipment. The kobolds should be equipped as normal for their level (reference the miniatures' cards if you have them) except the warriors have masterwork light crossbows built for Small characters.

Relevant Skill Checks

Disable Device DC 20: It's unlikely a PC will have the time or inclination to make this check, but a result this high allows the PC to jam the portcullis trap open, assuming it's open at the time the check is made.

Escape Artist DC 30: A PC who succeeds to this degree on an Escape Artist check can squeeze through the bars of the portcullis trap. See the squeezing rules on page 148 of the Player's Handbook. A Tiny or smaller creature can automatically squeeze through the bars. A Large or larger creature cannot move through the bars.

Listen DC 5: The PCs don't make this check. When they come within the hall-residing kobold's sight, he screams, and the kobolds in Area B make a Listen check to hear him so that they can set their trap in motion.

Listen DC 6: A kobold sits in the hall to the south, nattering absentmindedly to itself in Draconic as it waits for someone to come through the door. If the PCs make Listen checks outside the door before opening it, increase the DC by +5.

Listen DC 17: The kobolds in Area B are chatting in Draconic while they wait for someone to fall into their trap. If the PCs make Listen checks outside the door before entering, increase the DC by another +5. If a PC hears the noise, it seems to the PC like it's coming through the southwest corner of Area A.

Search DC 10: A Search check with this result can reveal the holes through which the portcullis bars fall, although if the PC does not have the trapfinding ability, he does not necessarily know their purpose.

Search DC 20: Getting this result on a Search check allows the PC to discover the secret door in the south wall of Area A. The door can be opened simply by pushing. It swings both ways easily but with a loud squeaking noise as it turns on its rusted pins.

Spot DC 16: A PC standing under where the portcullises fall can spot the small holes in the ceiling that the bars drop through or the holes in the floor that they fit in when fallen. A PC making the check from a distance suffers the normal penalties, so the effective DC to see the holes of the first portcullis for a PC standing just inside the door would be 24. PCs charging or running down the hall after the kobold should not be allowed to make a Spot check.

Speak Language (Draconic) DC --: A PC who speaks Draconic can understand the kobolds when they talk to one another.

Strength DC 10: This result allows a PC to aid another (granting a +2 bonus) in the following Strength checks.

Strength DC 24: This check result allows a PC to bend one of the iron bars. This give PCs trying to move through the bars a +5 bonus on their Escape Artist checks.

Strength DC 30: A Strength check this high allows a PC to break one of the iron bars free from its moorings. This allows any PC up to Medium size to squeeze through the bars without the need of an Escape Artist check. See the squeezing rules on page 148 of the Player's Handbook.

Alternatively, a PC who makes a Strength check to lift the portcullis and gets this result can actually lift a portcullis into the ceiling (causing both of them to rise), but the portcullises remain up only if the PC continues to make the check on the following rounds or the lever is pulled up. A PC who loses her grip on the raised bars or intentionally lets go without them being secured is attacked by the trap as the portcullises come down again. Note that if a bar is bent by the PCs, the portcullises can't be lifted until the bar is bent straight again.

The Map

The map for this room is available in two different sizes: One serves as a reference for the DM, and the other is a map with a grid that works nicely with your miniatures.

Each map is presented as a compressed (zipped) Adobe Portable Document Format file (pdf). You need to have Adobe Reader installed to use it. Adobe Reader can be downloaded for free from the Adobe website.

This encounter works best with a party a level or two below the EL. Large area-affecting spells such as fireball can make short work of the kobold warriors, so it's best to spring this trap on 4th-level characters.

Read this text if the PCs open the stone door leading into the area.

You heave open the stone door, revealing a small room and a long hall leading into the darkness to the south. A puddle in the northeast corner is the only remarkable feature in the room. Otherwise it bears the dust, scrapes, and pock marks common to many other parts of the dungeon. As you glance about the room, you hear something from the darkness of the southern corridor.

The PC should make a Listen check at this point. See the Relevant Checks sidebar.

The PCs are about to walk into a trap. A group of kobolds has claimed this area of the dungeons after learning how to use a secret door and a portcullis trap in the halls. The puddle in the northeastern corner of the room (Area A) is kobold urine micturated by the kobold sitting on the floor in the corridor to the south (K). The kobold is absentmindedly talking to itself in Draconic about its allies and how he hates having to stay in the hall while they relax. When the PCs enter, the kobold hears the door and prepares himself to stand up and run, but he doesn't get up until he can see the PCs since he's not certain the door opening isn't one of his fellows playing a trick on him.

When a PC comes within range of his darkvision, the kobold screams and stands up. At this point, you should ask the players to roll initiative. Roll initiative for the kobold in the hall separately from those in Area B.

The kobold in the hall has a job to do: He must wail pathetically and run to the south, luring the PCs after him and alerting the kobolds on the other side of the wall that the trap should be set in motion. The kobolds in Area B should make DC 5 Listen checks to hear their fellow in screaming in the hall. Assuming they do, half of them run to the south and the other half run to the secret door that leads into Area A.

The kobolds' plan is simple: Allow some or all of the PCs to move between the portcullises and then pull the lever that activates the trap. Then the kobolds in Area A mob any stragglers and both groups shoot crossbows at PCs between the portcullises. They even have a table looted from another room that they can push into the corridor from the south and use as cover. The tricky part, of course, is the timing. The kobold in the hall runs to the south, stopping to turn around just after he passes under the second portcullis. If attacked by the PCs before that point, he does his best to get out of the hall before his fellows drop the portcullises. The kobolds heading south from Area B can run and reach the lever (and pull it) in 2 rounds. (One pulls it while the others grab the table and start moving it into the hall.) The kobolds heading through the secret door get to it with a single move and then Listen to see if the PCs have run down the hall (DC 10 Listen Check assuming the PC aren't attempting to move silently). If the PCs wish to use their Move Silently skills, the DC of the Listen check is opposed by the Move Silently result as explained in the Player's Handbook on page 79, though the Listen check DC has a modifier of +10. If the kobolds don't hear the PCs, one opens the door on the following round and they flood in to attack anyone not caught in the trap.

Portcullis Trap: CR 1; mechanical; lever trigger; manual reset; Atk +10 melee (3d6, piercing); Search DC 10; Disable Device DC 20.

The two portcullises fall at the same time when a lever is pulled. Each trap attacks any creatures in the squares below it when the lever is pulled. A PC attacked by a portcullis must then decide which side of the portcullis to end up on, north or south, since the portcullis blocks movement through the hall. (Of course, a PC killed or rendered dying by the trap doesn't make it to one side or the other.) Pulling the lever doesn't require a Strength check. Clever PCs might use a mage hand spell on the lever, causing the portcullises to immediately rise, but the kobolds send them crashing down again at the earliest opportunity.

Each iron bar of the portcullis has a hardness of 10 and 60 hit points. The bars are about 6 inches apart. See Relevant Checks for more information.

Kobold Skirmishers (9): See page 161 of the Monster Manual or use the statistics for the Kobold Skirmisher (35/60) from the Dragoneye miniature set. The kobolds are armed with masterwork light crossbows for Small characters, giving them a +4 ranged attack that deals 1d6 points of damage. Note that some of the kobolds might take cover behind corners or behind the table in the south. Also, keep in mind the range of the kobolds' darkvision when making ranged attacks (unless the PCs carry a light source). Six kobold skirmishers head south. Three head north with the kobold soldiers and kobold champion.

Kobold Soldiers (2): These kobolds are 2nd-level fighters. Use Table 4-16 in the Dungeon Master's Guide and the advice on page 127 of that book to generate the kobold fighters or use the statistics for the Kobold Soldier (44/60) from the Angelfire miniature set.

Kobold Champion (1): This kobold is a 4th-level fighter. Use Table 4-16 in the Dungeon Master's Guide and the advice on page 127 of that book to generate the kobold fighter or use the statistics for the Kobold Champion (37/60) from the Aberrations miniature set {{link href="/default.asp?x=products/dndmin/966240000"}}. This is the kobolds' leader and the two soldiers are his lieutenants. As long as he is alive, the kobolds are unwilling to retreat, but should he fall, the kobolds run as soon as the number of PCs outside their trap exceeds their own numbers.

Treasure: The kobolds' equipment and goods are the only treasure.

Adventure Hooks and Tie-Ins

  • The kobolds aren't interested in making coup de grace attacks. They just want to take the PCs' gear. If the PCs fall to the encounter, another band of adventurers might hear the ruckus and arrive in time to drive off the kobolds and heal the PCs. Then the PCs can track the kobolds to their lair and, with the help of the NPCs, regain their stolen gear.

  • This encounter becomes more dangerous if another monster lays the trap. Consider replacing the kobolds with goblins, orcs, hobgoblins, or bugbears.

Need more information? Check the Return to Undermountain: An Introduction for more details.

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About the Author

Once editor-in-chief of Dragon Magazine and now a game designer at Wizards of the Coast, Matthew Sernett wrote in a Dragon editorial that there's nothing in D&D he likes better than when the adventurers flee through the dungeon, running pell-mell through traps and past monsters because what chases them is worse. When he wrote that, Matthew was thinking about Undermountain.

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