Originally Posted by
Daeron
The ring contains most of Sauron's power and he's one of the most powerful Maiar. He created it to try and control the bearers of the three elven rings. But how much power it gives to someone else depends entirely on whether that person or creature has power of its own. There are only a few in the LotR who could actually pose a serious threat to Sauron if they'd had taken the ring. Aragorn, Galadriel, Saruman, Denethor, Gandalf, maybe Faramir and of course Elrond and a few Elf lords. And because most of Sauron is in that ring and he is one of the greatest Maiar, all of those would be corrupted by its very nature.
Magic in LotR is for the most part quite different from what we see in Marvel. Finrod Felagund had a sort of magic battle with Sauron in the second age that was in the form of two opposing songs. Luthien sang everyone including Morgoth (the original evil) to sleep with a song. Gandalf is shown using words of command though, he never really sings, but because he has power, there is power in his words.
Arda itself was created by Eru in a song with the Valar, Maiar and other spirits and its said that when the world is broken, the spirits of men will join Eru in a second song to create a new and perfect earth. That's why unlike elves, men are not immortal, they leave the world completely to join Eru while elves are bound to it and won't take part in the creation of the new world, but will maybe get to live in it.