Lightning Bolt is one of those spells that strikes fear into whomever it targets. A massive damage output combined with a sort of AOE along with an impressive range makes this a great option.
The rules for Lightning Bolt can be found in the Players Handbook on page 255.
Lightning Bolt 5e
Casting Time: 1 Action
Range: Self (100 Foot Line)
Components: V, S, M (a bit of fur and a rod of amber, crystal, or glass)
A stroke of lightning forming a line 100 feet long and 5 feet wide blasts out from you in a direction you choose. Each creature in the line must make a Dexterity saving throw. A creature takes 8d6 lightning damage on a failed save or half as much Damage on a successful one.
The lightning ignites flammable objects in the area that aren’t being worn or carried.
At Higher Levels: When you cast this spell using a spell slot of 4th level or higher, the damage increases by 1d6 for each slot level above 3rd.
The description for Lightning Bolt outlines why the spell is so popular as an alternative to other Damage heavy spells like Fireball. It deals significant Damage to more than one target. The downside is getting the same type of effect with a much more difficult setup. The Damage is only dealt in a line.
How much Damage does Lightning Bolt do?
Lightning Bolt is comparable to Fireball in the amount of Damage it does in terms of dice, at a massive 8d6 at the base cast with an additional 1d6 per level upcast. The Damage is halved if the creatures in the target line succeed on a dexterity saving throw.
This makes Lightning Bolt incredibly powerful and a bit more precise than other high damage options. Of course, getting the full Damage out of as many targets is significantly harder as it only goes in a straight line.
Does Lightning Bolt go through Objects?
This is an objectionable position that can have arguments made for and against. The spell states that objects that are flammable, not worn or carried, are ignited. This would indicate that it does pass through those objects, setting them ablaze. The spell also doesn’t specify that anything blocks it, such as X-feet of wood or stone. 5E is very specific as far as what spells can and can’t do in the description.
The practicality, on the other hand, is a bit of an issue. If nothing stops a 100-foot-long blast, it could be shot through several rooms of a dungeon or castle, which makes little sense. This would indicate that objects do stop the bolt if they are not flammable. The spell also doesn’t specify that it travels around corners or walls as other spells do either.
Ultimately this comes down to situation and DM interpretation.
What Level Spell is Lightning Bolt?
Lightning Bolt is a 3rd level spell. For the time that it becomes available, it is a decent option. It has good range, deals significant Damage, and can hit more than one enemy. When considering the third-level spells, the caster has some choices to make as Fireball, Animate Dead, Counterspell, and Dispel Magic are all also available.
The full caster classes get access to some pretty significant spells as 3rd level spells. Many of them are important, and making that decision may depend on the role taken in the party.
Thinking about the party composition when choosing spells can be important. Depending on the type of characters the caster is with, Lightning Bolt may be a good alternative if other members have access to fire-based attacks. Lightning is resisted less than fire so having a change-up is not always a bad thing.
Can Druids Learn Lightning Bolt?
Lightning Bolt is only available to the Wizard and Sorcerer base classes. The Arcane Trickster Rogue and the Eldritch Knight also have the ability to acquire it. In addition, special iterations of the Artificer, Druid, and Warlock have access to the spell.
The limited access to the spell reduces the possibility of overlap and is another reason to consider taking it over some more commonly shared spells.
There is absolutely nothing wrong with playing a Wizard or Sorcerer who doesn’t take Fireball as long as you take Lightning Bolt. The spell is high Damage and AOE, which are two things that the party relies on from a full caster at later levels.
This makes a spell like Lightning Bolt all the more important. Just remember the potential unintended effects when casting around flammable objects. The last thing you want to do is to burn down the village you are trying to save with a Lightning Bolt intended for the BBEG.