John Constantine

"Bloody Hell! you're a wanker!" - Constantine to Banner

Syponis
(born May 10, 1982),[1] alias El Diablo among the gangsters of Mexico City[2], is an exorcist, demonologist and hedge warlock, self-styled as "master of the dark arts". Raised in an abusive orphanage who saw him responsible for the death of his mother in childbirth, (who was the most beloved worker at the orphanage), John grew up highly cynical and cunning, and developed an interest in the dark arts. In his teenage years, he was introduced into the occult world by Anne Marie, learned various spells and became an exorcist with the hopes of one day using his powers to resurrect his mother. John became a figure of respect among the dabblers of magic.

Avengers
After realizing Loki uses magic, Fury decides to call in an "old friend", which Maria realizes who he's referring too. At 2012, he was living in Highbridge, The Bronx, New York. He was approached by Natasha Romanoff, who recruited him to defeat Loki