Mattie

Mattie is a member of Band Blunders. Mattie has appeared in Kenny as the main protagonist. She has recently starred in Music Madness as well. Mattie has stated that she does not plan on appearing in any more movies, other than a brief scene in Kenny II: New Reed.

Films
Mattie appears in Kenny as the main protagonist and 'Final Girl'. She appears in Music Madness as a quaternary protagonist. She is suspected to be the villain for most of the film.

Music Videos
The Band Blunders videos that have Mattie in them are mostly music videos. Her first appearance was in Lemon, NeXus, and Gag go to Afghanistan as a featured appearance. Her thing was running into walls. Her second appearance was in one of the most popular videos on the channel: Dance Till You're Mattie (ft. Gage). This video features clips of Mattie dancing to Dance Till You're Dead, with a few scenes showing Gage pushing her out of frame. A sequel, Dance Till You're Mattie 2, this time featuring Liam, follows the same premise, but with a different Dance Till You're Dead remix and almost all new scenes of Mattie dancing (a few iconic ones from the first one are reused briefly).

Band Blunders Movie 1 and Friends
Her next appearance was in Band Blunders Movie 1, an ASDF Movie style video. In it, she does the Dame Tu Cosita dance and knocks Liam unconscious with a red pipe.

Her most recent appearance was in the Friends video, a video that displays all of the currently active Band Blunders to the Friends theme song. Mattie's scenes are her doing the Dame Tu Cosita dance, her Fortnite video on Kelsey's YouTube channel, and her flipping sunglasses onto her face, as seen in the picture above.

Kelsey's Channel
Kelsey's YouTube channel features two videos with Mattie. Clips from these two have been used in Band Blunders. The first one is called IT 2018 BETTER. This video is a tribute to Pennywise, and features Mattie and Kelsey doing the Pennywise dances and acting like Pennywise. Most of the clips from Dance Till You're Mattie came from this video.

The second video is called Fortnite Remix Final. This features a live-action Fortnite video, with Mattie and Kelsey playing Fortnite in real life. Liam also makes a cameo at the end as the final enemy who is shot by Mattie.

Relationships

 * Raina - Mattie and Raina seem to be on and off with their 'kind mood', as demonstrated in Kenny, when Raina and Mattie fight over sitting on her store shelf, but then, they also help save each other during the windstorm.
 * Liam - Mattie and Liam seem to coexist well. They tend to be on and off with their 'kind mood' too, but tend to meet and achieve their goals, whether that is creating a music video or stopping an evil saxophone from killing people.
 * Rebekah - Mattie and Rebekah seem to be friends at an okay level. They don't communicate much, but their friendship is proven strong when Mattie cried when Rebekah was stabbed by Hunter in Kenny.
 * Hunter - Not positive. They have only been around each other when Hunter was evil.
 * Kenny - Love/hate relationship. Kenny hates Mattie, but Mattie loves him more. Confusing.
 * Raquelle - Contact was never made. She died too fast. Completely unexpected.
 * Kimi - Mattie reveals in Music Madness that she doesn't feel Kimi likes her very much compared to Liam and Raina.

Band
Mattie is in band, but she was not present for the inciting incident of Band Blunders.

Instrument
In Kenny, Mattie plays a trumpet, even though it sounds awful. This was done on purpose, as proven by the message in the ending credits, stating, "Mattie is actually a good trumpet player, despite what you heard earlier.".