So, why not. I'm going to create a dwarf druid that breaks the rules on druids. First off, they will wear metal armour. Their excuse: there are no trees in a mountain, and stone is very uncomfortable. They will be very fine with chopping down trees and that. Their excuse: the whole purpose of druids is to nurture life. What is my purpose of I have nothing to make grow? What do you think? What would you do if I were your DM?

I find subverting tropes by simply doing the opposite of what you expect as boring as just using the tropes, especially when you do it with all the tropes of the subject. Besides, what is the use of calling a thing a certain name if it doesn’t match that name?

Maybe flipping one would make an interesting character. But, I still think that finding some creative way to do a new take on a Druid doesn’t require just breaking the things that make them druids. 

But I’m sure you’ll still have fun role playing the character and that is all that matters. 

Wearing metal armor is an interesting take but i don't think druids can wear any armor that is "metal"? unless your going for cosmetic and have metal pieces which is fine.

I think the best way to imagine druids are very savage tribes who care nothing for nature as it is a tool for their own survival, they have no need for caring for the forest or care if it burned down to the ground. They live life as savage as it can be for it is the proper way of life. Though you could say the druid simply prefers using whatever it takes to keep themselves alive, they embrace on the basic of kill or be killed and use whatever it takes to gain the edge over any difficulty.

If i were to DM you, i'd ask you a question: How did you obtain your druidic powers? is it a something given to you by a source or or is it learned like regular magic? each one can lead to a different way on handling such character:

- if it's by a source i'd say nature (or some unknown god of wilderness that lives within the material plane) is a mysterious force that had chosen your character for not necessarily a reason but simply for what your character is or what will be.

- if it's something learned then it's much simpler.... it is something learned not by words or texts it is learned by embracing existence and the will to live.

This is my take on it hope it helped you a little bit.

Thanks, bit I asked 'what if I were your DM', so you'd be my player. How would you feel about this druid?

Oh sorry i misread it!

The concept does seem to be good and interesting but then again, i'll need to play it to really find out, after all a character won't come truly to life without other players that i would interact with and how you as a DM deal with it. Don't worry the concept has a great potential and it isn't bad by any means if that what you are afraid of.

I don't think most people should be able to give you an informed opinion unless you answer some questions. What is the point of this NPC? Does the fact that he breaks all the rules add in any way, to what he actually believes or does as a Druid?

Quote from BramblefootDruid >>

So, why not. I'm going to create a dwarf druid that breaks the rules on druids. First off, they will wear metal armour. Their excuse: there are no trees in a mountain, and stone is very uncomfortable. They will be very fine with chopping down trees and that. Their excuse: the whole purpose of druids is to nurture life. What is my purpose of I have nothing to make grow? What do you think? What would you do if I were your DM?

 My feels about that, especially with the 'explanations' would be: the concept is not very well thought out. First, Druids live within the ecosystem they originate from. In this case this seems to be the mountains. Even though, higher mountain ranges do not offer any trees or plants you can make armour of, you can still use hide armor, nothing is stopping you from doing this. So, in my opinion this is a weak excuse for using metal.

Second, in my opinion, druids go with balance of nature, so trees have their right of existence. Furthermore, mountains do have a flora, which mainly consists of scrub trees, small bushes, plants, grasses, lichens, mosses, algea, etc., so there is something growing in the mountains. Not respecting plant life would be very strange.

I would not feel comfortable with that specific druid concept.

Sorry I couldn't type out lots on a phone (it hurts). I guess the idea is that there are reasons for a druid being different. 

I try to come up with something in my mind... how about a druid from the elemental plane of mineral or magma? Would probably still allow Hide armour, but it goes more in that direction.

Or something weird from one of the lower planes? Druid of Limbo?

Not thought out yet, but why not... 

Quick note: at least in older editions, it was explained that druids didn't avoid metal armor because it was metal, but because it had been tempered/forged, so its natural energy was "off."

If your the DM you can do what you want.

My question is......If one of your players came to you with that idea as a Player Character would you allow it? If not why?

I would allow it. DnD is a game, where we make characters to escape the rules of the modern world. I don't mind if a character 'breaks the metal armour 'RULE'. Because we can customise our characters. Hope this is understandable, and it's a good enough reason.

I know I'm really late to the party on this thread, but in case it's still relevant, if I were a player, I wouldn't like this NPC at all. It feels cheesy and gimmicky, like a joke character, and I don't usually enjoy joke characters in my games. Maybe your players do enjoy silly NPCs, though, in which case, go ahead!

Not that my opinion matters but, I am glad to see you would let your players do the same! Understood & good enough response for me :D

How about a warforged druid that takes wildshape like a transformer. A robot whose was built to protect an area from poachers or whatever has gained druidic abilities. Im sure with a robot you could find plenty of reason why traditional druid traits are out the window.

Well, I think there is something to your idea.  Other posters have pointed out some issues with the particular justification you gave, but keep working on it.  BTW here is the sage advice column about druids and metal armor.

What happens if a druid wears metal armor? The druid explodes.

Well, not actually. Druids have a taboo against wearing metal armor and wielding a metal shield. The taboo has been part of the class’s story since the class first appeared in Eldritch Wizardry (1976) and the original Player’s Handbook (1978). The idea is that druids prefer to be protected by animal skins, wood, and other natural materials that aren’t the worked metal that is associated with civilization. Druids don’t lack the ability to wear metal armor. They choose not to wear it. This choice is part of their identity as a mystical order. Think of it in these terms: a vegetarian can eat meat, but the vegetarian chooses not to.

A druid typically wears leather, studded leather, or hide armor, and if a druid comes across scale mail made of a material other than metal, the druid might wear it. If you feel strongly about your druid breaking the taboo and donning metal, talk to your DM. Each class has story elements mixed with its game features; the two types of design go hand-in-hand in D&D, and the story parts are stronger in some classes than in others. Druids and paladins have an especially strong dose of story in their design. If you want to depart from your class’s story, your DM has the final say on how far you can go and still be considered a member of the class. As long as you abide by your character’s proficiencies, you’re not going to break anything in the game system, but you might undermine the story and the world being created in your campaign.

TLDR: the taboo against wearing metal is a story element, and if your particular story has a justification for druids wearing metal then you are perfectly within your right to have them wear metal armor. 

Anyway, what is is that you are really trying to do?  Are you trying to make a group of really interesting dwarf druids that are unique?  If so, then there is probably a better way to do it than just saying "they wear metal" and thinking up a flimsy excuse.  I have a dwarf druid i'm playing in a campaign that wears half plate, but it's made of a carapace from a creature from the underdark.  So I would think about your dwarf druids and figure out how their culture works.  If their culture includes a greater acceptance of civilization, then maybe they wear metal.  But dwarven druids probably wouldn't like typical dwarven civilization based on the traits dwarves usually possess.