The One Ring, Variant (5e Equipment)
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A golden ring with an inscription that when in fire translates to "One ring to rule them all, one ring to find them, One ring to bring them all and in the darkness bind them." The ring has no definite shape and can change its size to fit the wearer. The ring has a level of malevolent sentience, giving it a neutral evil alignment.
Power of the ring The One Ring grants the user a massive amount of power. While the user wears the ring their lifespan becomes indefinite, until life becomes too tiresome for the user.
The ring also makes the user give off an aura that makes them appear more powerful to others, giving them +5 intimidation. Though the form the bearer will be seen as is unclear, previous ring bearers have appeared as a warrior cloaked in shadow, or a figure robed in white holding a wheel of fire. Often the form will inspire fear in creatures that are not skilled in magic, causing them to flee. Only those with true sight can see through the illusion.
While wearing the ring, the user is able to become effectively invisible. The wearer casts only a thin shaky shadow that is only discernible in the brightest of sunlight. However, the use of this ability does not come without risk, as the ring's use will attract the Nazgul, also known as ring wraiths or dark riders. These riders seek the one ring for their master, Sauron (or the evil master in your campaign), and will kill anyone or thing that stands between them and the ring. It should be noted also that those who can see the non-physical realm, can still see the wearer, such as the Nazgul.
These powers of the ring are the few known to mortals, as most mortals cannot access the true potential of the ring, due to their weak minds and wills. It would take a disciplined, well-trained mind with great native power for one to even begin to tap into the true power of the ring. Even still, it would take time to master the ring in order to become as powerful as someone like Sauron.
Casting the ring into the fires of Mt. Doom is quite the perilous journey as many forces seek to return the ring to its master. The travel to destroy the ring can take as long as six months, depending on the circumstances. The nature of the journey alone can cause unrest in any group and corruption can only worsen things. Before one can destroy the ring, in order to reach Mt. Doom, the bearer or bearers must travel through Mordor, the land of Sauron and his minions. Traveling through Mordor is no easy task as there are only two known entrances: The Black Gate and the Pass of Cirith Ungol. Both are equally dangerous with Sauron's forces watching the black gate and the lair of the giant spider, Shelob, awaiting at the pass, alongside the proximity to Minas Morgul and Dol Guldur, Sauron's strongholds. Truly, one cannot simply walk into Mordor.
As mentioned, during the journey evil forces will seek the ring. Often when around evil forces that work for Sauron (or the evil master in your campaign) and being worn by the bearer, the ring will expand suddenly to escape from the wearer and return to the hands of evil. To avoid losing the ring, it is best to not be worn and kept on a chain. Should the ring attempt to slip away, a DC 15 dexterity check must be made by the wearer to successfully recapture the ring. Should the wearer not catch the ring, all other party members and sentient beings may make an attempt to grab the ring as well, once again making a DC 15 dexterity check.
Should the ring be returned to Sauron, then he shall gain ultimate power and seek to rule all the free peoples of the world as God. Those who seek not to worship him will be exterminated, such as the elves, who would never do so as worship Sauron. The details of Sauron's desires are mostly unimportant, but it should be noted that a terrible new age will begin should the ring fall into his hands.
Should a different evil master be used in your campaign, this will greatly complicate things, as a story and land must be made for the master, as well as a volcano to destroy the ring.
Though the Fate of the ring often is clear, the fate of its bearers is often less so. Often a bearer of the ring dies because of corruption of the mind making the ring their obsession, which usually leads to their inevitable demise. Those who do not die may go on to live a normal life, should their exposure to the ring have been minimal. Most who live however, go on to live a life of torment from the physical and psychological scars the ring and the quest to destroy the ring leave on one. It is even possible that a bearer who lives after the rings destruction could lose their sanity, leading them to a life of isolation and agony.