D&D 5E Low-level Party going Underwater.

[Dan Chernozub]

I'm running a homebrew campaign, and the party of 5 level-4 characters has decided to explore the underwater tunnels.

They have gotten their hands on a supply of water-breathing potions. I'm looking forward to limiting their gear for this adventure. The tunnels are not deep, but it seems reasonable to me that characters will have to leave some of the heavy stuff behind (like, you know, they like to carry a few dozen feet of steel chain around just in case). I'm also thinking to have them leave behind books and scrolls (magic or not).

Any other restriction/limitation ideas? What can go wrong with your standard adventuring gear after being immersed into the water?

 

[Valmarius]

Don't forget that fighting underwater is tricky. It's all difficult terrain and only a select few weapons won't be striking at disadvantage.

Also, if it's dark underwater they can't use torches for light. Darkvision/Light cantrip will be useful here, but might not be available.

 

[discosoc]

Don't go overboard on trying to simulate the difficulties of exploring and fighting underwater. Otherwise it's a rabbit hole of problems. Just keep to the basic system of granting disadvantage to most melee attacks (other than maybe thrusting attacks), no ranged, limited vision, and very slow movement. It can make for fun and challenging encounters, especially against enemies better suited to the environment, but it will probably get old fast.

 

[Dan Chernozub]

Don't forget that fighting underwater is tricky. It's all difficult terrain and only a select few weapons won't be striking at a disadvantage.

Also, if it's dark underwater they can't use torches for light. Darkvision/Light cantrip will be useful here, but might not be available.

Yeah, I've looked through the underwater fighting rules first thing.

The illumination is a nice thing to note, especially with 4/5 of the party being humans. Cleric has a Light cantrip (he is a Light Cleric, in fact) - but it might draw some attention to the explorers.

Don't go overboard on trying to simulate the difficulties of exploring and fighting underwater. Otherwise, it's a rabbit hole of problems. Just keep to the basic system of granting disadvantage to most melee attacks (other than maybe thrusting attacks), no ranged, limited vision, and very slow movement. It can make for fun and challenging encounters, especially against enemies better suited to the environment, but it will probably get old fast.

No range at all you suggest? I think it was auto miss at long range, a disadvantage for all but javelins and crossbows at short range.

I'm not planning to keep them underwater for long, or for all the time. They going to a partially submerged Temple.

It seems to me that picking up the ground for a fight might very well be an interesting part of their next adventure. Definitely not every enemy in the temple will be good at aquatic combat.

What I'm trying to think is if there are any equipment/gear restrictions that I'm missing that could make sense.

 

[Yunru]

Unless they're actively swimming, what's stopping them from just talking all their stuff (that they don't mind getting wet at least) and walking through like normal?

 

[discosoc]

No range at all you suggest? I think it was auto miss at long range, a disadvantage for all but javelins and crossbows at short range.

You're call, but keep in mind that ballistics are trash underwater. A modern compound bow can launch an arrow maybe 10 feet, but there's really not enough power to pierce much past a few of those feet. For a best-case scenario, consider how modern spearguns usually operate in the 3-7 (about 25 feet max) meter range, which is a far cry from the crossbow "short" range. Not to mention crossbow bolts are nothing like speargun shafts, so they are going to tumble after a few feet anyway. Basically, ranged weapons really aren't viable underwater in most scenarios, and certainly not when using normal "land" versions.

 

[Dan Chernozub]

Totaly makes sense for me. I just wanted to stick to the rules as much as possible since this is my first 5e game.

Interesting how ranged spells should function. Will probably rule it with a case-by-case approach.

 

[discosoc]

The thing with magic is that casters generally need to be able to recite incantations, perform precise physical manipulations, and interact with reagents. About the only one of those that seems remotely possible would be the second one, or somatic. That said, Jeremy Crawford's tweet on the matter was simply "Being underwater doesn’t prevent spellcasting." So if you want to just allow it, at least it's in line with the theme of 5e being incredibly basic and letting anything happen.

 

[Dan Chernozub]

Well, aquatic races do have spellcasters, right? I agree that things should be more difficult for land-dwellers.

I think at least some spellcasters can get away with Material part via focus.

I don't want to completely shutdown our wizard, though.

Any ideas/suggestions on how to implement those difficulties without banning Verbal spellcasting outright?

 

[Oofta]

For spellcasting: it depends on how you see a potion of water breathing working.

Water is turned to air when it enters the mouth, you should be able to perform the verbal components.

It literally allows you to breath water then it depends on if you think the vibrations of the vocal cords still works with water. It also has the interesting side-effect of the users coughing up lung-full of water when the spell wears off.

In either of those two scenarios it would be difficult at best to protect most of your gear from getting wet.

The easiest ruling is that potions of water breathing envelopes you in a bubble of air keeping you and your equipment dry.

On a related note, I also have to agree that I don't see a reason to limit equipment unless people are swimming.