Griff Tannen

Griffin Thomas Tannen is the secondary antagonist of Back to the Future: Part II. He is Biff Tannen's future grandson and the bully of Marty McFly Jr..

He was portrayed by Thomas F. Wilson, who also played Biff in the film.

Biography
In the year 2015, Griff has his own gang of bullies by his side, and has a dysfunctional relationship with Biff as he complained against him of getting one wax instead of two on his car. When Marty, Doc Brown, and Jennifer were head to the year 2015, Doc Brown told Marty that his future son Marty McFly Jr. was going to be arrested thanks to Griff for getting him involved in a robbery. Marty disguised himself as his own son to prevent this from happening.

Cafe 80's
When Marty goes to the Cafe 80's, he encountered both old Biff and Griff, who turned out to be Biff's grandson. When Marty Jr. went inside the Cafe 80's, Griff mistakenly thought that Marty Jr. had left the Cafe. Griff and his gang of bullies tried to convince Marty,Jr. to join them to a robbery. Not taking "No" for an answer, Griff both abuses and tosses Marty Jr. around. With Marty,Jr. knocked out, Marty took his place and said "No" to Griff and tries to walk away. Since Griff doesn't take "No" for an answer, he called Marty "Chicken," and tried to hit him with a retractable bat. Marty managed to escape both Griff and the bullies.

The Hoverboard Chase and Defeat
Marty borrowed a little girl’s hoverboard to escape the gang. After ending up in a lake, Marty’s hoverboard stopped because it doesn't work on water. Griff then took out his own hoverboard as Data, Spike and Whitey follow him, hoping that Griff will smack down Marty with the bat. Griff then tries to hit Marty with his bat, only for Marty to intentionally drop himself into the water, causing Griff to lose his balance, and also causing Griff and his gang to crash into the courthouse.

Data, Spike, and Whitey are last seen being arrested along with Griff for their actions. This alters the future timeline and prevents Marty Jr. from getting arrested. Even Biff, who had witnessed the events, called Griff and his gang a bunch of “buttheads” for their foolishness, possibly feeling that his grandson got what he deserved.

Quotes

 * Griff calls Marty 'chicken'.: What's wrong, McFly? Chicken! (As Marty walks towards the door, he stops when he hears this) (One of Griff's gang makes a clucking noise) (Marty: What did you call me, Griff?) Chicken, McFly! (Marty furiously turns around and throws his cap off his head) (Marty: Nobody calls me..) (Griff raises his baseball bat) (Marty:(nervously)...chicken.)
 * Griff to "Marty McFly Jr.": Batter up!
 * Griff's last words as he is arrested.: I was framed!

Trivia

 * He serves as the antagonist for the first quarter of the film and is responsible for Doc traveling to 2015 along with Marty and Jennifer to save their child's future.
 * Jeremy Irons, Harry Shearer, the late Robin Williams, Chevy Chase, John Malkovich, and Mandy Patinkin were all considered for the role of Griff before Thomas F. Wilson was selected.
 * With the 2015 future being rewritten, it is unknown if Griff Tannen still bullies Marty Jr.
 * Griff is the only version of Biff Tannen to have a female gang member.