Is it possible to use a Mordhau grip to deal bludgeoning damage?

Question

I play in a short D&D 5e campaign, with many undead type monsters, like skeletons and the like. My character has a Longsword, which deals slashing damage.

Now I would like if it would be possible to take my sword in the "Mordhau Grip" (basically grabbing the sword on the blade and using it to strike with the grip and shaft), to deal bludgeoning damage, because of the weakness from skeletons to bludgeoning damage.

Would this be possible, and would I get the same damage and/or debuffs or the like on my attack?

Answer 1

RAW, no, but a DM might allow it

Rules as Written, the longsword does slashing damage, and there are no rules that suggest otherwise (i.e. no weapon property that allows a different damage type), so it cannot deal bludgeoning damage.

However, if it seems reasonable to your DM, they might allow it. If I were your DM, I might allow it if your character had already seen other party members dealing bludgeoning damage and generally doing better for it, then roleplaying a brief scene where your character's like "Hmm, I can smash bones easier than I can cut them, maybe I should try holding my sword like this?", but ultimately whether this is allowed depends on each individual DM (some may allow it without any roleplay to justify it in-game, some may disallow it regardless because that's not RAW).

That said, if I were to allow it (and therefore if other DMs were to allow it, they may well rule the same), I would do as Erik's answer suggests; since, although one can use a sword in this way, it is not designed to be used in this way, so it should use the improvised weapon rules, which means it would do 1d4 bludgeoning damage instead of 1d8 slashing damage.

Answer 2

You can use the rules for Improvised Weapons

Sometimes characters don't have their weapons and have to attack with whatever is at hand. An improvised weapon includes any object you can wield in one or two hands, such as broken glass, a table leg, a frying pan, a wagon wheel, or a dead goblin.

Often, an improvised weapon is similar to an actual weapon and can be treated as such. For example, a table leg is akin to a club. At the DM's option, a character proficient with a weapon can use a similar object as if it were that weapon and use his or her proficiency bonus.

An object that bears no resemblance to a weapon deals 1d4 damage (the DM assigns a damage type appropriate to the object). If a character uses a ranged weapon to make a melee attack, or throws a melee weapon that does not have the thrown property, it also deals 1d4 damage. An improvised thrown weapon has a normal range of 20 feet and a long range of 60 feet.

Specifically, a sword held by the end of the blade might (at the DM's discretion) resemble something like a club or a hammer, and use the stats for it (including dealing Bludgeoning damage).

Worst case, you'd have to use it as an actual improvised weapon, which will still deal 1d4 bludgeoning damage, which might still end up being more effective than using the normal damage die due to doubling the damage rolled (and your modifier!) to a vulnerable target. You will lose proficiency to hit, but if you hit, it'll be worth it.

Answer 3

The weapon properties: Ammunition section specifically says that using ammunition (or a loaded sling) as a melee weapon makes it count as an improvised weapon. That's probably the right way to handle it any time you're using a weapon in a way that was not intended (or at least not the primary intended way). That should apply to throwing a sword, using a mordhau grip or pommel strike, or striking with the back of your blade (if you're using a singled-edged weapon, of course).

Normally, the only reason for this kind of thing would be to either deal a specific type of damage or alter the range of a weapon. In this particular situation, I'd probably say a sword wielded in this way counts as a mace.