10. Shinigami Eyes – Death Note

The powers of Death Note were already bestowed upon Light Yagami but even it wasn’t sufficient enough until Ryuk came up with the trading system of “Shinigami Eyes”. In order to obtain the shinigami eyes, one must strike a deal with a Shinigami or the God of Death and trade half of his/her remaining lifespan to get access to this powerful ability.

Whether it is a random person’s name or how long someone would live, the Shinigami Eyes can give users access to both. This pair of eyes helps its users see the lifespan and name of a person floating right above their heads. The only downside of this ability is that you cannot see your own lifespan. And, it becomes destructive after being combined with Death Note.

9. Faustian Contract – Black Butler

Faustian Contract is a deal made by Ciel Phantomhive with a demon named Sebastian, whose powerful abilities and charm Ciel utilizes as a means to avenge his family. When a deal is made, a seal is placed on the body of the human so that the human cannot escape. In Ciel’s case, it was placed in his right eye however, the marked eye doesn’t really have a power of its own as it is more of a symbol.

Although, Ciel’s eyes aren’t the most powerful eyes in anime still it acts as a symbol of the bargain as it makes the demon Sabastian always at his service. Being a demon he’s extremely powerful acquiring all sorts of abilities ranging from blood manipulation, extraordinary senses, and speed, to immortality. And, as a matter of fact, Ciel usually covers his eye to keep the Faustian contract and his true intentions secret.