I'm the DM in a 1E game, I'm an old grognard, in which a 4th level character lucked into a helmet with True Seeing, 3x per day. When at all possible I like to let the chips fall as they may.
Me dilemma is that that an NPC very close to the party is a lycanthrope and the stage is set for a future betrayal as part of the story line.
I'm inclined to treat True Seeing as able to reveal the lycanthrope for what it is only when it is shaped changed out of it's human form, and not the reverse. In other words a large evil looking wolf would be revealed to be a lycanthrope but a large brute of a man wouldn't be. Well he's not a brute really but he is quite hairy with a bit of a sloped forehead and yellow eyes ( the party hasn't suspected anything in spite of this description). I realize the interpretation is up to me but I'm curious if others think I am overreaching or even mistaken.
It lets you see their "true form", and humanoid is considered their true form per their stat block, so the rules back you up. (In 5e for sure, but I'm pretty sure the same applies to previous edition rules as well.)
These forums are mostly for 5e. Rules as Written in 5e, true seeing says the following "and perceives the original form of a shapechanger or a creature that is transformed by magic."
It doesn't see the "true" form of a creature - it sees its "original" form. In the 5e monster manual it says "In its natural humanoid form, a creature cursed by lycanthropy appears as its normal self." From this perspective, the original form of a lycanthrope would be it's human form so in 5e, true seeing would reveal its original form without shape changing. However, if the creature has changed as a result of the lycanthropy "Over time, however, many lycanthropes acquire, features suggestive of their animal form." If this has occurred, I would tend to think that true seeing would show the original version of the person. They might not appear quite as hairy or their eyes might not be yellow for example.
So, from a 5e perspective, I think you'd be fine giving away little or no information on the NPC as a result of true seeing.
However, if you are playing 1e, it is likely a different story.
"Polymorphed, changed, or magicked things are apparent. Even the aura projected by creatures becomes visible, so that the cleric is able to know whether they are good or evil or between."
True seeing in 1e makes changed or magicked things apparent. In this case, a lycanthrope is clearly changed and a true seeing spell on a helmet in 1e would make the lycanthrope clearly visible and it would also reveal the creatures alignment.
So, although you'd probably be fine if playing 5e, the version of the ability in 1e was significantly more perceptive.
P.S. As a result, a lycanthrope in 1e might know this and have some sort of magic item they might carry that might confuse the effect of true seeing - alternatively, since you gave them the helm ... you get to deal with the consequences. :)
I'm the DM in a 1E game, I'm an old grognard, in which a 4th level character lucked into a helmet with True Seeing, 3x per day. When at all possible I like to let the chips fall as they may.
Me dilemma is that that an NPC very close to the party is a lycanthrope and the stage is set for a future betrayal as part of the story line.
I'm inclined to treat True Seeing as able to reveal the lycanthrope for what it is only when it is shaped changed out of it's human form, and not the reverse. In other words a large evil looking wolf would be revealed to be a lycanthrope but a large brute of a man wouldn't be. Well he's not a brute really but he is quite hairy with a bit of a sloped forehead and yellow eyes ( the party hasn't suspected anything in spite of this description). I realize the interpretation is up to me but I'm curious if others think I am overreaching or even mistaken.
Regards
I would handle it the same way you are.
"Not all those who wander are lost"
It lets you see their "true form", and humanoid is considered their true form per their stat block, so the rules back you up. (In 5e for sure, but I'm pretty sure the same applies to previous edition rules as well.)
These forums are mostly for 5e. Rules as Written in 5e, true seeing says the following "and perceives the original form of a shapechanger or a creature that is transformed by magic."
It doesn't see the "true" form of a creature - it sees its "original" form. In the 5e monster manual it says "In its natural humanoid form, a creature cursed by lycanthropy appears as its normal self." From this perspective, the original form of a lycanthrope would be it's human form so in 5e, true seeing would reveal its original form without shape changing. However, if the creature has changed as a result of the lycanthropy "Over time, however, many lycanthropes acquire, features suggestive of their animal form." If this has occurred, I would tend to think that true seeing would show the original version of the person. They might not appear quite as hairy or their eyes might not be yellow for example.
So, from a 5e perspective, I think you'd be fine giving away little or no information on the NPC as a result of true seeing.
However, if you are playing 1e, it is likely a different story.
"Polymorphed, changed, or magicked things are apparent. Even the aura projected by creatures becomes visible, so that the cleric is able to know whether they are good or evil or between."
True seeing in 1e makes changed or magicked things apparent. In this case, a lycanthrope is clearly changed and a true seeing spell on a helmet in 1e would make the lycanthrope clearly visible and it would also reveal the creatures alignment.
So, although you'd probably be fine if playing 5e, the version of the ability in 1e was significantly more perceptive.
P.S. As a result, a lycanthrope in 1e might know this and have some sort of magic item they might carry that might confuse the effect of true seeing - alternatively, since you gave them the helm ... you get to deal with the consequences. :)