Return to Undermountain
Room 10: The Winding Way (EL 10)
By Matthew Sernett

Room Summary

Creatures: (15) Twelve ophidians, two clerics of Bane, and one bright naga.
Traps: (13) Water rush traps bull rush creatures off the causeway.
Terrain: Normal, although the causeway top and sides are damp.
Lighting Conditions: Darkness.
Magic: None except treasure.
Detectable Alignments: Faint evil (ophidians and bright naga) and strong evil (clerics of Bane).
Secrets: None besides the traps.
Treasure: The clerics of Bane carry their equipment, and the bright naga has amassed a small cache of coins and jewelry worth about 500 gp.

Relevant Skill Checks

Climb DC 15: A PC that grabbed the side of the causeway after falling off can clamber back onto it with this result.

Climb DC 25: A PC can Climb the slippery side of the causeway with a successful Climb check.

Bluff DC (Opposed): A PC speaking in Yuan-ti can claim to be one and might intimidate the ophidians.

Disable Device DC 20: This result allows a PC to disable one of the trapped sections of the causeway.

Intimidate DC (Opposed): A PC speaking Yuan-ti and successfully bluffing that she is one can intimidate the ophidians into leading the PCs to the bright naga and the clerics. However, the ophidians refuse to leave the bright naga unprotected and accompany the PCs deeper into the bright naga's lair.

Listen DC 13: Ophidians scale the sides of the causeway even as the PCs look into the room. Remember that distance modifies the DC (+1 per 10 feet of distance from listener). An ophidian nears the edge of the causeway beside each "O" marked on the map. A PC who succeeds at the check hears a snakelike hissing and a scratching noise off the sides of the causeway.

Search DC 15: This result allows a PC to discover a trapped square on the causeway.

Sense Motive DC 15: A check with this result reveals that the ophidians are trying to avoid stepping on certain parts of the causeway when they move.

Spot DC 23: Ophidians scale the sides of the causeway even as the PCs look into the room. Their chameleonlike ability to change the color of their skins makes them difficult to see. Remember that distance modifies the DC (+1 per 10 feet of distance from spotter). An ophidian nears the edge of the causeway beside each "O" marked on the map. A PC who spots an ophidian is not surprised.

Swim DC 10: This is the DC to swim through the water beneath the causeway.

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.

Room Location on the Poster Map: This room is on piece 4 of the poster map. You can see the pieces in thumbnail size in the introduction to this series. For a better idea of where this room is, please view the Article Reference Map.

This encounter works best if the PCs are a couple levels lower than the EL. An area-affecting spell like lightning bolt or fireball can make quick work of the ophidians on the causeway. If this happens and the PCs are having an easy time with the encounter, consider having more ophidians climb up from below.

When the PCs look into the room, read this text:

A damp causeway covered in puddles of water stretches across this chamber to a doorway on the far side. To either side of the causeway lies a long drop into darkness. From the gloom below you can hear water splashing. To either side of the causeway stand walls that reach 20 feet up to the ceiling above. The walls on either side of the causeway have holes large enough for a man to crawl into. It's hard to tell from your vantage point, but it seems like the holes don't go far into the wall before they turn downward.

Note: The drop is so deep that even a dwarf's darkvision cannot reveal what would stop a fall, so DMs should mention this if a party member has such vision.

Have the players make Listen checks and Spot checks. A PC that succeeds at the Spot check is not surprised when the ophidians slither onto the causeway. Read the following text:

Suddenly several snakelike beings slide up onto the causeway from its sides. Even as they do so, their skin changes color from the grays and black of the damp stone to a ruddy orange. They draw swords and hiss a challenge at you.

PCs who failed their Spot checks are surprised, but the ophidians make no immediate move to attack. Instead, the first one waves with his sword in a threatening and challenging manner for the PCs to approach. The ophidians are guarding their mistress, a bright naga in counsel with two clerics of Bane several rooms away.

The ophidians speak Common but they can't be reasoned with or tricked unless someone speaks to them in Yuan-ti and claims to be a member of that race. This gives them pause, and successful Bluff and Intimidate checks convince them to lead the PCs to the bright naga and the clerics. The cowed ophidians explain the workings of the causeway and its dangers, and they escort the PCs, some going ahead to alert the bright naga of the "yuan-ti" visitors and others moving ahead and behind the PCs. Should the PCs keep this ruse going, it confuses both the naga and the clerics of Bane, allowing the PCs the element of surprise.

If the PCs talk for too long or start spellcasting, the ophidians nearest the entrance move to attack and the other ophidians file forward, all of them being curiously cautious to step in the diagonals. This gives their movement across the causeway a serpentine appearance that could be mistaken for their natural inclination, but a DC 15 Sense Motive check reveals they're trying to avoid certain areas of the walkway. Stepping in those areas (marked with an X on the map) results in the activation of a trap. See "Water Rush Traps" below for more details.

The two clerics of Bane have come to the bright naga's lair to convince her to undertake the ritual to become a banelar naga (see page 72 of Serpent Kingdoms). If the naga converts to worship of Bane, they intend to use her and her ophidian minions to guard a secret temple to Bane being carved out of Undermountain. Even now, they have hired adventurers working to clean out an area of monsters so that they can construct defenses and repurpose that area of the dungeon. The two clerics and bright naga come running as soon as a water rush trap is set off. They arrive in 4 rounds and enter the combat.

Water Rush Traps: CR 1: mechanical; location trigger; automatic reset; Bull rush +6; Search DC 15; Disable Device DC 20.

Each square marked with an X on the map is the trigger for hundreds of gallons of water to come rushing out of a hole in the wall to spray across the causeway over the two adjacent squares to the east. Thus, as someone moves across the causeway to the west, water sprays through the squares behind that person with each step onto a trapped square. The trapped squares cause a rush of water only when first depressed. Therefore, any creature stepping on a trapped square causes a rush of water when it first enters the square, but the water then ceases until the weight is removed and then put on the square again. It takes 10 pounds of pressure to cause a rush of water.

A creature in a square through which a rush of water passes is subject to a bull rush attempt. The water pushes with a +6 bonus on the opposed Strength check. If the water wins, the PC is pushed back 5 feet. If the water wins by 5 or more, the PC is pushed 10 feet. A PC pushed off the causeway may make a DC 15 Reflex save to grab the edge. Failure results in a fall to the water below (see Falling or Diving Off the Causeway).

The ophidians, clerics of Bane, and bright naga all know how these traps work and what squares are safe to step on. They use the traps to their advantage, staying off the trapped squares until a foe steps forward into the spaces the water would spray through. Whether a PC moves in front of or beside his foe, the PCs' foe need only 5-foot adjust to a nearby square to set off the trap and send a water rush to push the PC off the causeway. Of course, a PC might tumble or simply move around an ophidian, a tactic they are at first unprepared for, but then they stand side-by-side to block the causeway and step on and off the trapped squares to use the water against the PCs.

Make sure to keep track of the PCs' movement on the causeway. They too can set off the traps, and if they are not careful, a PC might end up accidentally setting off a water rush trap so that it affects another PC.

12 Ophidians: See page 133 of the Fiend Folio or use the statistics for the Ophidian (57/60) from the Angelfire miniature set

1 Bright Naga: See page 55 of the Miniatures Handbookor use the statistics for the Bright Naga (45/60) from the Dragoneye miniature set.

2 Clerics of Bane: Use the statistics for the Cleric of Bane (35/60) from the Archfiends miniature set. If you don't have that miniature, use Table 4-14 in the Dungeon Master's Guide to design two 5th-level human clerics.

Falling or Diving Off the Causeway

The water 70 feet below the causeway is 30 feet deep, so any creature falling off the causeway takes 3d6 points of damage plus 1d3 points of nonlethal damage. A creature deliberately diving off the causeway can make a DC 20 Swim or Tumble check to take no damage.

The ophidians have long practice turning falls off the causeway into dives. Due to their ability to take 10 on Swim checks despite distractions, the ophidians never suffer damage for falling or diving off the causeway. However, if affected by something that penalizes a Swim check (such as diminishing the ophidian's Strength), an ophidian must roll a Swim check when falling from the causeway because taking 10 will not be sufficient.

Adventure Hooks and Tie-Ins

  • If the PCs don't succeed in killing the clerics and the naga, the clerics use the PCs' intrusion to reinforce the naga's need for more power and protection. She agrees to the ritual that will make her a banelar naga, and the clerics of Bane assign her first task as a disciple of Bane: Hunt the PCs down and destroy them.

  • The clerics of Bane are building a secret temple beneath Waterdeep! Perhaps one of the clerics carries a note to this effect that alerts the PCs to the danger. The PCs might need to find a group of adventurers somewhere else in Undermountain and convince them they're doing the work of the church of Bane, or they might have to defeat a group of mercenary adventurers that knows and does not care that they're working for evil. Alternatively, maybe disguised clerics of Bane hire the PCs to clear out an area of Undermountain under some false pretense.

  • If you'd like to make this encounter tougher on the PCs, consider turning the bright naga into a dark naga (Monster Manual page 191). A CR 8 dark naga would raise the EL to 11.

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

Article Reference Map

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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