Tunnel of Death (3.5e Encounter)
From D&D Wiki
Encounter: tunnel of death
- CR 4
- Integration any underground campaign
- Prep Time 30min
- Play Time 10-60 mins
A hole in the floor droops 20 feet (1D6 fall damage) into fast moving water. A small ledge near the water can be reached by jumping from a rope or swinging. When in the water (Strength checks of 14 each round or be washed away). Anyone who is swept away by the water will have one last chance to grab a broken rusty iron drain cover gate (DC 16 reflex save). If they fail to grab the gate they will end up in the crocodile infested waters after passing through a long tunnel that has almost no air pockets. The broken rusty Iron Gate has a large hole in it as if something swam up the underground drain pipe and broke through it (a large snake did and is waiting in the next chamber.)
The roof of the water tunnel is covered in roots and can be used to climb down the tunnel climb check DC 12, there are piousness snakes in the roots search check DC 22, the poison paralyses 1d4 rounds normal bit attack Fortitude saving throw DC14. These small but very poisonous snakes poison differ from the ones in the monster manual other stats are the same. Drowning Any character can hold her breath for a number of rounds equal to twice her Constitution score. After this period of time, the character must make a DC 10 Constitution check every round in order to continue holding her breath. Each round, the DC increases by 1. When the character finally fails her Constitution check, she begins to drown. In the first round, she falls unconscious (0 hp). In the following round, she drops to -1 hit points and is dying. In the third round, she drowns.
Anyone who enters the water must make Strength checks of 14 each round or be washed away. If the players tided themselves together with a rope +2 per each person to DC if the person behind you falls and is being washed away -1 on your DC drowning rules apply. You move at one quarter speed and the water is 4 ft high making it difficult for shorter players to move or breath. Swim check of DC19 if anyone try’s to swim. Average move is 30ft X 4 + 120 in one round / by 25% = 30 ft. pre round the water tunnel is 90ft so three rounds if no other action is taken. The trick to this tunnel is to make a simple thing like traveling 90ft. becomes a challenge the players may try to go over the water using the roots but will soon find it is infested with poisonous snakes. The water has its own challenges with being washed away. When my D&D group played this it took about 45 mins for them to cross the tunnel they tied themselves together and just about every round someone would fail there strength check and fall the party would have to stop and aid the person in getting up some times traveling backwards to help the player before they drowned.