A single copper coin that is attracted to those with little money, such as beggars. If you are greedy and investigate the copper piece on its own before touching it and beat a DC 20 Investigation check, you can get a premonition that the copper piece will bring you ruin if you touch it.
Origin. The history of the Bad Copper is foggy, as the item is obscure by design and obfuscates its own existence. Any creature of utter greed can tell you, however, of the tale of the Great Equalizer. Legend says that a Good god came down to a city overcome by greed to see if the inhabitants had any hope left. They came upon a beggar who had recently become one, after their modest living proved not to be enough to live in their already modest home. They begged and petitioned for any kind soul to give them a single copper piece. Three days of begging came and went, and the beggar received nothing but scowls and yells to get a job. The god, pitiful of this person, took their soul up to their Good plane of existence, but as the beggar's body fell, the god made hundreds of copper coins spill out of a bag they kept on their person. Immediately, everyone who was around the beggar pounced on their corpse for the money, tearing their body apart and killing each other for a single copper, even the people who had millions of platinum pieces to their name. But what they did not know was that each coin was cursed with the god's righteous anger, and when they returned to their homes, they discovered that all of their money came to dust and ashes. They wept and cried, not in repentance for their sin, but for their loss of finances. The god, seeing these mortals beyond any redemption, abandoned the city to its fate, save a few repentant souls. These coins were lost to history, but show up now and then to humble the greedy and empower folk heroes to topple greedy governors.
In Good Hands. A Bad Copper appears in the possession of beggars who are at the end of their rope in desperation. Upon finding it, the beggar will find that worthless trash in their vicinity tends to transmute into gold coins that other creatures can only see on a DC 20 Perception check. So long as this money is used to give them and others a higher station in life, it will continue to turn trash to gold. The moment the former beggar's heart feels that the Bad Copper is a tool for themselves only, or a greedy person steals the Bad Copper from the former beggar, Miser's Downfall triggers until that person atones for their sin.
Miser's Downfall. If a creature with a flaw that makes them inhumanly greedy, such as a dragon of any type or just a greedy individual of a species, touches the copper piece, every single piece of currency the creature owns burns - even if immune to fire - into ashes. Only a Wish spell or Divine Intervention can stop this, and only on one collection of currency. Any new currency the person acquires immediately is destroyed the same way. The creature is branded on its face with a mark that any other greedy person recognizes as divine vengeance on that person, and they're not likely to interact in a positive manner to their presence. Certainly they won't have business transactions with you.
Atonement. To atone for their sin, the person must seek out a shrine belonging to the god that created the Bad Copper and beg for forgiveness. For the rest of their life, the creature must fight against greed and injustice against the poor, or at the least never be greedy again. The mark of punishment fades over 3 months after atonement. If ever they should be greedy again, the curse will afflict them again and the god will be much less likely to forgive.
Eternal Mark. It is trivially easy to physically destroy the coin once it has cursed a creature. The coin, however, is nothing but a transfer mechanism for the curse, which stays on the person, and the god may make as many of these coins as they desire.
You never stated which god created the Bad Copper...
Why an investigation check and not an Arcana check?
That is by design. This can be slipped into any campaign that way.
I use Investigation and not Arcana because Arcana is not Detect Magic or Identify. Investigation gives only a premonition that something bad is going to happen, not at all what that thing is. Think of it like getting a deadly premonition as opposed to understanding what the coin does.
*DM laughter echoes in the distance*
I love this idea! This is simply one of the best homebrew items I've read. However I do have one critique... This item is listed as an artifact despite the fact that there are many of this coin, and it does't have any artifact properties. I'm sorry if this was annoying, but overall I love the item! (maybe just change it's rarity to legendary)
This coin can literally never help people out of poverty, at least for a sustained period. It would severely inflate gold AND it teaches the impoverished to not work. If they ever lose the coin, they will lose all sources of income and return to poverty. I like the idea that the coin gives its (good) owner skill in any artisan's tools, those artisan's tools, and will continually produce the required materials, such as wood for carpenter's tools.
I think they meant the person who stole the Bad Copper from the person who's "In Good Hands" is the one that will suffer? As the curse should have passed on. There might need to be an update to state whether or not the curse stays with the "good" person if their coin is stolen, as they are not really a sinner still and shouldn't have to atone for anything.