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Monthly Encounter #17: A Whitefang in the sewers (lvls 1-4)

Here at Tribality, we’ve decided to provide our readers with Encounters ready to be added to your table. I’ll be creating new ones monthly for you to have a big collection to look through when you run out of ideas for your game. If people end up liking them we may start releasing them in easy to print PDF format.

Don’t forget to comment feedback or possible variations for others to see and/or possibly implement when running this encounter. Without further ado, hope you enjoy it:

Setting: Agnostic
Location: Urban
Lvls: 1-4

Encounter background

The city the adventurers are in has been dealing with a thieves’ guild for some time. After numerous tracking, the city watch has found that the thieves’ base of operations is probably located in the sewer system below the city. Two groups have been sent to investigate. The first group completely disappeared. The second one had one of the guards come back heavily scared. On top of having to deal with the thieves’ guild, there are also enormous crocodiles to deal with. One of them seems to be their leader, an albino one who is even bigger in size than the rest of them.

The albino crocodile has become a living legend between the guards, who now name it “Whitefang”. If they want to be able to deal with the thieves’ guild they need to get rid of the crocodiles. Luckily, the city is full of adventurers looking for work.

A Whitefang in the sewers

Adventure Hook

The player characters can receive the mission in a number of ways:

  • One or more of the PCs worked as a city watch in the past and is contacted for help.
  • The city governor sends a messenger to gather the adventuring party as it is gaining renown in the region.
  • PCs encounter a city watch coming out of the sewers crawling and pleading for help.
  • The characters see a post in a tavern from the city watch, who are looking for help granting a great reward in return.

Traveling through the sewers

There are several dangers to be found in the sewers. Read or paraphrase the following:

  • The dark and damp tunnels are filled with a nauseating stench. One corridor in each of its sides acts as raised platforms to walk through and avoid the mucky waters traveling in the center of the tunnel. Drops of water fall from the ceiling breaking the silence that is only accompanied by the flow of water coming from pipes on the side. Only one torch remains lit in the distance, with all other torches placed in sconces extinguished. 
  • The water keeps moving in one direction.
  • The torches can be easily lit again with fire.
  • (Illuminating the area reveals skull drawings on the right wall, used to help members from the thieves’ guild find their way back)

Torch. Torches in the sconces can be taken out to have while moving through the tunnels. Lighting a torch takes an action. There are sconces with extinguished torches every 30ft.
 Moving through the water is done at half movement unless the creature doing so has swimming speed. The water is at the same level as the platforms on its side, allowing those swimming on it to easily climb to the platform.

While moving through the sewers, each of the players have to roll a d20 for a possible encounter along the way. Each roll symbolizes 30 minutes of travel. On a roll of 16 or higher, an encounter transpires. If it is an odd number, the DM has to roll for the number of members of the thieves’ guild below. Otherwise, the DM rolls for the crocodiles making an appearance. If all players but one have already rolled, continue to the Whitefang section.

Thieves’ Guild

1d4 bandits and 1 leader of the group see the characters in the distance. Roll any die to determine who the leader is. On an odd result, it is a bandit captain. On an even result, a thug. Its leader is guiding the path as it is an elf with darkvision.

Upon seeing the player characters, the thieves will ask from afar what their deal is here. Player characters can convince the thieves they aren’t after them with a successful DC13 Charisma (Persuasion) check. Otherwise, half the thieves will run towards the characters to fight in melee range while the other half fights from as far as they can.

Player characters can interrogate or ask about the albino crocodile’s location. The thieves’ guild is taking advantage of the beast as it keeps the city watch away from their base, and the thieves have already learned how to remain far from it. A DC14 Charisma (Intimidation) check against a thief after a battle can have them point in the right direction, removing one of the encounters to be rolled. Failing on the check has the thief lie, pointing in the opposite direction and having the players add one more encounter roll to be rolled.

Encounter balancing: If the PCs are level 1 or 2, replace the leader with an extra bandit.

Treasure. The thieves are carrying with themselves satchels with a total of 1d10 gp and a golden giant coin with the symbol of the city valued in 20gp.


1d4 – 1 crocodiles and 1 giant crocodile move through the water. Upon seeing the player characters they move towards them and try to grapple and move them underwater, where they have the advantage. Trying to scare the crocodiles off requires a successful DC18 Charisma (Intimidation) check.

Encounter balancing: If the PCs are level 1 or 2, replace the giant crocodile with an extra crocodile.

Treasure. 1d10 intact crossbow bolts pierce the side of the crocodiles’ corpses.


The last encounter roll to be made actually indicates if Whitefang attempts to attack the player characters by surprise or if the player characters find it before it gets a chance of doing so. A result of 16 or higher has Whitefang roll a Dexterity (Stealth) check against the player characters’ Passive perception. Those with a lower Passive Perception score than Whitefang’s Stealth result start the combat surprised.

Whitefang starts the combat in the water and will try to grab and pull creatures underwater, where it has the advantage.

A white giant crocodile comes out from the water. Its body is massacred with scars aplenty and its right eye is of a bloody red color, bloodshot by a scar. The scales in its back are filled with dry blood with two handaxes and a harpoon stuck on it, as well as multiple broken crossbow bolts. A peculiar shining dagger pierces its right side, its blade still dripping a green liquid.

Whitefang is a giant crocodile with the following modifications:

  • Whitefang starts at max health (135hp)
  • Swift Swim. As a bonus action, Whitefang gains extra 20ft swim speed.
  • If Whitefang drops to 20hp or less, it will attempt to escape. It has survived many battles, and this will not be its last.
  • Whitefang contains action-oriented abilities, which can be done on initiative 0:
    • 1st round: Whitefang moves an additional 30ft without causing opportunity attacks
    • 2nd round: Whitefang moves an additional 15 ft., and does a bite attack. After biting, it rolls in its place, dealing 21 (6d6) piercing damage.
    • 3rd round: Whitefang submerges underwater and attempts to hide ( it gains an extra +5 to its Stealth roll). Additionally, it gains 50ft swim speed.

Encounter balancing: If the PCs are level 1 or 2, Whitefang initiates combat at half health (67hp).

Treasure. Two intact handaxes, a dagger of venom, and 10gp for each player character among the dead corpses from Whitefang’s lair.


The city watch awards the player characters for their bravery with 200gp. If the player characters did encounter a path to the thieves’ guild location and inform the city watch, they will award them with 100gp, and ask the adventurers if they would like to accompany them to raid the thieves’ guild in the future.

Additional details

In order to make combat encounters more fun and interesting, consider adding the following things to the environment:

  •  Pipes with levels next to it that can be pulled to increase the water pressure coming from it. Using an action to pull the lever deals 1d6 bludgeoning damage to all creatures in a line from it and pushes them 10ft.
  • Have some of the corridors near the water broken that have destructible wooden planks to “fix it”.
  • If the encounter is getting too easy, have an extra bandit hear the noise and appear to confront the player characters.
  • Have a crocodile show up while fighting bandits that attacks whoever is nearest to it.
  • Use 2MinuteTabletop free sewer maps for this encounter. They are gorgeous and work great! Sewer maps assets || Sewer Map Tiles

Sewer map from 2MinuteTabletop

Want more encounters?

If you liked this encounter and would like to see more check out the index I created with all the monthly encounters I’ve created so far, listed by tier lvl and environment: