J2:His real name is Zane Yama Marco. Yes, THIS Marco. He is the son of Cain Marco, the unstoppable Juggernault. At some point in his life, Cain Marco decided he wanted to settle down. He got married to a DA, had a son, and then dissappeared in another dimension.
Zane's mother decided she had to move on. But it seems that Zane had inherited more than just his father's name. He had also inherited his powers. So, he made up a costume out of his father older one, and took the name J2.
Now, he is a member of the new Avengers, and he is trying to clear his father's name.