Simon (The Walking Dead)

This unnamed Savior is a character in the AMC television series The Walking Dead. Though no official name has been given to him yet, he is credited as the Lead Savior. 

He serves as the secondary antagonist in the Season 6 finale, "Last Day on Earth". Overall, he serves as the quaternary antagonist of the second half of Season 6 and as the possible tertiary antagonist of Season 7. He is a high-ranking member of The Saviors and is one of Negan's right-hand men, along with Dwight.

He is portrayed by Steven Ogg, who is most famously known for portraying Trevor Phillips in Grand Theft Auto V.

Season 6
This unnamed Savior was first encountered when he and a band of others Saviors hunt down a man in the woods. They then mercilessly beat him and drag him to a road, intending to show him to Rick's group as a warning. When Rick and his group arrive at the scene in their RV, they are stopped by a roadblock made by this Savior's group. He orders Rick to hand over their belongings and when refused, this Savior says that they will not negotiate and their deal is the only deal. The Savior then warns Rick about what will happen to those who oppose Negan and recommends him to treat his friends like it was their last day on earth, knowing full well what Negan is going to do with them.

He is encountered once again in the climax, when a large group of Saviors ambush Rick's group in the woods. He then orders them to hand over their guns while threatening to shoot Carl. He also orders Dwight to go get the rest of the group that were captured earlier. After Rick and others are forced to line up and get on their knees, the Savior knocks on the RV and summons Negan himself to make an entrance. When Negan asks which one is the leader, this Savior points at Rick, telling him that he was the main responsible for the death of his men. He is present when Negan makes his speech and beats one of Rick's group to death with Lucille.

Season 6

 * 6x16: "Last Day on Earth"

Season 7
(TBA)