D&D 5E Magic weapons granting tremorsense, rather than shedding light: balanced?

[Whizbang Dustyboots]

This feels like it's roughly balanced, since generally speaking, having a light source is more useful. (It's hard to read the inscriptions in an underground tomb with tremorsense.) But I haven't ever seen this in play, as I recall, so maybe I'm off here.

Would you allow this substitution on a weapon, DMs?

 

[Sorcerers Apprentice]

Not even remotely balanced, tremorsense is way better. There are plenty of other ways to get light, but few if any ways of getting tremorsense. And tremorsense can also help detect invisible enemies, and works even in magical darkness.

 

[Whizbang Dustyboots]

Not even remotely balanced, tremorsense is way better. There are plenty of other ways to get light, but few if any ways of getting tremorsense. And tremorsense can also help detect invisible enemies, and works even in magical darkness.

How about a cursed weapon that grants tremorsense but also blinds the attuned wielder?

 

[Sorcerers Apprentice]

How about a cursed weapon that grants tremorsense but also blinds the attuned wielder?

That sounds fun!

 

[el-remmen]

I like the second idea better, but would limit it to when it is being wielded.

 

[humble minion]

Balanced, absolutely not. Interesting, definitely. I have to wonder, after all, why dwarves or drow would craft magic weapons that shed small amounts of light. They have darkvision so it's of very little help to them, but it does mean that the weapon can be spotted from well outside darkvision range, so it's a definite negative and they'd probably go out to avoid it. Still, the light property of a magic weapon isn't really intended to be a practically useful effect, it's intended to obviously flag to everyone looking that This Weapon Is Magical.

If you want to tone it down a bit (tremorsense is very powerful after all), perhaps something like advantage on Perception checks involving hearing? Or perhaps while the weapon is being wielded, the wielder's voice is boosted and they can speak louder or be heard at greater distances?

 

[Quickleaf]

This feels like it's roughly balanced, since generally speaking, having a light source is more useful. (It's hard to read the inscriptions in an underground tomb with tremorsense.) But I haven't ever seen this in play, as I recall, so maybe I'm off here.

Would you allow this substitution on a weapon, DMs?

Agree with others that it's not a balanced 1 to 1 substitution.

If you really wanted to have a weapon grant tremorsense, there are some ways you could curtail the power to make it closer to being balanced...

• You could have the tremorsense only recognize certain types of creatures, such as a dwarven axe that only senses goblins.
• You could have the tremorsense only function in a specific biome or in a specific location, such as an elven bow whose string vibrates (flavor for the tremorsense) only in the Deep Wilds.
• You could make it a limited use thing similar to the One D&D Playtest for dwarves (i.e. action to activate, lasts 10 minutes, can use a # times per day = proficiency mod).
• Similar to above, but instead of defining a # uses, you could impose a risk after the first use, like the ring of x-ray vision, e.g. "Whenever you use the tremorsense again before taking a Long Rest, you must succeed on a DC 15 CON saving throw or gain one level of Exhaustion."

 

[niklinna]

Or it worked only if 1 creature other than you was within the range, otherwise the signal's too muddy.

 

[Umbran]

I like the second idea better, but would limit it to when it is being wielded.

You mean, the curse is that you are struck blind, in general, and the tremorsense only happens when you are wielding the weapon?

 

[EzekielRaiden]

Personally, I don't think you would need to make it a permanent curse.

If the weapon is actually "worn" (as in, it can be drawn easily), then the wearer is blind. So long as they have the weapon in hand, they have tremorsense to a limited range--perhaps 15 or 20 feet. Enough to be valuable. Not enough to replace proper sight. Genuinely doffing the weapon (dropping it and not touching it, stowing it away in one's pack, etc.) allows one's sight to return over the course of 10 minutes. The 10-minute delay prevents players constantly dropping and picking it up to minmax the blindness effect.

If you have concerns about that, make it an attunement thing. Only people attuned to the weapon get any benefits or detriments at all--to anyone that isn't attuned, it acts as a perfectly mundane, albeit durable, weapon. Once attuned, it works as above. (This would be best if you're worried about your players trying to use the weapon's "cause blindness" effect against their enemies.)