No, he isn't, but the spirit trapped inside the Fierce Diety Mask is. When wearing this mask and transforming into Oni Link, Link doesn't become evil, he just inhabbits the powers of the Fierce Diety.
I think ryu became evil due to the power of the satsui no hadou that oni has, oni passed it on to ryu making ryu evil, i might be wrong but thats what i think happened, hope i helped
Literally: "Demon" or "Evil Spirit"
The oni is the demon of Japanese folklore. It takes on many other names, sometimes referred to as a devil. Unlike most western cultures, the oni is not necessarily seen as an evil being. It is said to be of a dual nature, meaning it's powers can be good or evil, depending on if it likes the subject it attaches itself too. Oni are credited with with bringing good health, safety, peace and avoiding disaster. A typical oni mask has horns, bulging eyes, a sinister looking smile and sharp teeth. Sometimes, it is shown in a form that looks more like a skull. This represents a very black and white image of transition. A representation that good is leaning toward evil, or that evil is trying to become good. Often, oni masks will have hair. If one could break away from the traditional impression that the demon is an instrument of evil, it would make the oni a more widely accepted good luck symbol.
You can only do that with Action replay.
No, Link never turns evil. Never.
Demon as in "devil" is "akuma." Demon as in "evil spirit" is "youkai."
One place that Oni appears in Ao Oni is in the library.
A few 1st tier games based on Ao Oni are Abe Oni, Aka Oni,Akame Oni, and Ao Oni Plus.
It is thought that the Oni is inside the mansion because he was a former resident of Ao Oni.
The Oni in Ao Oni is a creature with light purple skin and large black eyes.
I believe they are available from the start. I think you have to buy them... otherwise it depends onwhere you get it...
When an Oni starts following you in the game Ao Oni, the only place to hide is in a closet.