Friday Encounter: Rickety Bridge

Here's a simple environmental puzzle that forces players to rethink how they manage their inventory and how they approach obstacles with limited resources at their disposal. It could be used either in a dungeon, on the road, or in a wilderness environment.

The party will find their path is suddenly blocked by a deep chasm, with steep cliffs plunging 200 feet below. The only direct route across is via a rickety rope bridge - and it is obvious that it will not be able to accommodate a great weight. The PCs will likely have to leave heavier gear behind in order to get across.

It is best to tell the players the mechanics of this encounter so that they can make informed decisions about how they want to approach it. The bridge cannot bear weight greater than 300 pounds; if a load of 300 pounds or more crosses the bridge, it will automatically collapse, sending any creatures on the bridge plunging into the abyss. Furthermore, creatures bearing a load greater than 200 pounds will need to tread carefully in order to avoid putting undue stress on the ropes. For a creature bearing a load of 200 pounds to cross the bridge, they must make a DC 10 Dexterity check, or the bridge will break under their feet. For every additional 10 pounds they carry, increase the DC by 2. A creature bearing less than 200 pounds can cross the bridge without issue.

A "load" here should include the creature's weight and the weight of any equipment it is carrying or wearing - if you don't know exactly how much your character weighs, assume 150 pounds for a medium-sized creature, 75 pounds for a small-sized creature, 100 pounds for a dwarf, and 175 pounds for a goliath. A creature of large size or greater will automatically cause the bridge to break; a creature of tiny size or smaller can cross the bridge without incident.

There are a few ideas at play here. In order to make progress across the chasm, the PCs will likely have to abandon equipment, including heavy armor, treasure, and other useful things, as well as any horses or beasts of burden they may be traveling with. Whatever is on the other side, they'll have to deal with it without such assets. In a hostile environment, there may not be a guarantee that their equipment will still be where they left it if they return to the other side of the bridge to reclaim it, and the presence of such items piled up on the ground may tip enemies off to the PCs' presence nearby. Even if the PCs feel the risk of crossing the chasm is too great, such an obstacle can encourage them to seek out alternative routes, which might cause them to focus their exploration elsewhere. And if the bridge does break, now the remaining PCs will likely have to find another way around anyway!

By default, a fall from the bridge will almost certainly kill most PCs, unless they have access to feather fall or similar effects. However, you could also shorten the drop and have another area to explore below the bridge (or, conversely, change the fall to a drop into a spiked pit). Another option would be to replace the chasm with a rushing river, which could carry PCs - or their gear, if they attempt to ferry it across - downstream.