Last Updated on July 15, 2022
Swords are great, right? But wouldn’t they be better if they were bigger?
Maybe you’ve had this thought because you’re new to 5e but have played older editions of D&D, or maybe you’re just a fan of unrealistically massive anime weapons.
Either way, you probably have questions. The rules for larger weapons aren’t super complicated in 5e, but they aren’t super obvious either.
Here’s how to run oversized weapons officially and some options for unofficial methods as well.
There are two main places to look for oversized weapons rules; player abilities and monster rules.
Players have two main abilities that let them wield large weapons and that change their base damage die. The spell Enlarge/Reduce suggests that larger weapons provide only +1d4 to the weapon’s base damage.
Meanwhile, the Rune Knight subclass for fighters allows fighters to become Large with Giant’s Might.
This adds 1d6 and then 1d8 extra damage to your weapon and unarmed attacks. Later you can become Huge and deal an extra 1d10.
However, on page 278 of the DMG, there are rules for the oversized weapons that monsters wield (this video also talks about this).
Basically, those rules state that a weapon that is larger than medium multiplies the base damage die of the weapon per size category.
Large weapons let you roll double the number of weapon die, Huge weapons let you roll triple, etc.
That’s a lot better than Enlarge/Reduce, and if your players get a hold of such large weapons, it could seriously unbalance the game.
The DMG provides two solutions for this. First of all, weapons of a size category larger than the wielder impose disadvantage on attack rolls.
Optionally, a character might not be able to wield a weapon two or more sizes larger than them at all.
I recommend that the optional rule be enforced since otherwise, the penalty for wielding a gargantuan weapon and a large one is the same.
Still, D&D doesn’t stack disadvantage, so this isn’t as hefty a penalty as it could be (you fight the same blindfolded as seeing with oversized weapons).
It does mean that you can never gain advantage with the weapon, only cancel out your disadvantage.
For some DMs, this might still be too unbalanced. After all, a character who has been enlarged with the spell could technically wield a large weapon with no penalty!
Thus enters homebrew and the lessons of past editions to (maybe) provide a better route.
Homebrew and Older Editions
One homebrew rule people sometimes use is allowing disadvantage and advantage to stack. That is, for every source of advantage or disadvantage, you roll an extra die.
Of course, that can get unbalanced quickly in the right situations, but it does discourage taking a larger weapon for a numerical advantage since disadvantage stacking can be really painful.
Another option is to implement 3.5/Pathfinder’s rules for weapon sizes. In those editions, weapons that were larger (or smaller) would move up and down a scale of damage die.
Pathfinder’s weapon die scale: 1, 1d2, 1d3, 1d4, 1d6, 1d8, 1d10, 2d6, 2d8, 3d6, 3d8, 4d6, 4d8, 6d6, 6d8, 8d6, 8d8, 12d6, 12d8, 16d6.
Anytime a weapon increases in size, you would simply move one position up this scale (though in 5e the higher end is unlikely to ever be used).
This allows for a more graduated damage progression rather than skipping from 2d6 to 4d6 immediately upon moving up a size category.
D&D 5e is pretty hostile to players wielding oversized weapons with higher base damage, and it’s easy to see why.
Double base damage is the kind of thing that can completely overturn party and game balance in one go.
Challenges strong enough for one character will wipe another, and it will take an experienced group to manage it correctly.
If you want to use oversized items in your group, I recommend tweaking the rules a little. The homebrew options above are a good place to start, but don’t be afraid to keep messing with it.
Oversized weapons can be great for flavor, but they take careful management to implement.
The most important thing is to not be afraid of an unbalanced situation. Talk to your fellow players, including your DM. If changes need to be made, make them!
After all, D&D is a collaborative problem-solving and story-telling experience, and sometimes the problems to solve are “how to wield a massive sword taller than me and almost as wide.”