Lightning Water Post Icon
I’ve been working on an underwater adventure for my campaign. One of the characters is an Elemental Savant sorcerer focused on lightning. Naturally I began to wonder what rules existed in 3.5E D&D for electricity spells underwater.

It turns out, none. At least there are none in the SRD, and I haven’t seen any in supplements. So I set out to find a good solution.

In my opinion, any good rule should do the following:

  • Add to the enjoyment of the game. If ultimately the rule does not make the game more fun at the end of the day, it is not serving a worthwhile function.
  • Behave with verisimilitude. Note that this is not the same thing as behaving realistically. Many aspects of D&D are not realistic, but they do feel “right”, and that’s good enough. Falling damage doesn’t increase the heavier you get, or assume you fall at anything other than a flat rate, etc. However, this would be unfun and too complicated to model.

Players don’t really blink an eye at a magic lightning bolt defying physics in the air, but I bet anyone who goes to cast the same thing underwater experiences a cringe and expects something a little more volatile to happen. That’s what I mean by verisimilitude: it’s what you expect to happen, it has the appearance of reality, but is designed to be playable and fun.

It seemed to me there were several possibilities:

  • No change. It’s magic, right? Magic makes the lightning bolt go where you want in air (which is a fickle medium for electricity), and because electricity is conducted more easily by water, it just behaves magically.
  • Enhanced damage. Not my favorite, this just ups the power level and encourages a lot of lightning underwater.
  • Changed discharge shape. The spell becomes a cone or a burst, as the electricty is conducted more widely by the water. Perhaps with a wider area the spell deals less damage, as the energy is dissipated in a larger space.
  • Changed discharge shape, hurting the caster with the out of control electricity.

I didn’t really like any of these implementations, so I asked D&D guru Jediwiker for his opinion. He suggested the spell becomes a burst, emanating 5′ from every square it would normally pass through (including caster).

Stormwrack, the sea adventure supplement published by WotC, has rules for fire spells underwater. Fire spells are impeded the same way certain spells are in the Outer Planes (e.g. chaotic spells on strongly lawful-aligned planes). Impeded basically means the caster must overcome a certain difficulty on a Spellcraft check or lose the spell.

This option is good because it allows the player to overcome difficult situations through use of abilities. It is similar to giving a golem a high Spell Resistance, instead of spell immunity.

However, I didn’t like the idea of lightning fizzling underwater. Water doesn’t stop electricity, it just makes it behave differently. So I combined the rules with the burst-emanation idea, to get the following:

For spells with the [Electric] descriptor, the area of affect changes. The spell becomes a burst spell, emanating 5′ from every square affected by the original spell, and the spell’s damage is halved. For example, shocking grasp becomes a burst centered both on the caster and on the touched creature. Lightning bolt becomes 10′ wide swath (depending on how its aimed), affecting the caster as well. Ray attacks affect every square they pass through.
The caster may make a Spellcraft check (DC 15 + spell level) to have the spell conform to its original shape.

These rules shouldn’t cripple electric spells underwater (some become arguably better, such as scorching ray with electricity substituted as long as the caster has a resist or similar effect). The game should be a little more volatile, and by using a key class ability the caster can choose to fight the effect. Dc 15 + spell level should be reasonable for mid to high level games, where I’d say most underwater encounters occur.

Of course, by creating rules for one type of spell you may open a can of worms. Perhaps players demand to know what happens to [Acid] spells. Do they work normally? Hang in the water creating a “cloud” type of effect? And so forth.

So what are your experiences? In games you’ve played or run, have there been special rules for electric spells underwater? Did you find it fun or obnoxious?