Tails Doll

Tails Doll is the personification of all the bad Sonic games and loves to make people play horrible games and watch them suffer. He was only around the time when the reviews were still labeled as Super Gaming Bros. with both Johnny and his brother Elliot, but when it became just Johnny and the reviews became less flashy, he hasn't been seen since. He finally fully returned in the Ghost 'N Goblins & Super Ghouls N' Ghosts review, where he decides to give up but wants to see Johnny go mad before he leaves. To that end, he reappears in the Donater's marathon & makes Johnny play a game that terrified Johnny' s younger self... Ecco the Dolphin.

All of these acts, along with his undying hatred for Johnny and Elliot, make the Tails Doll the unofficial main antagonist of the Somecallmejohnny channel.

Origins
The Tails Doll is one of the first of the many things to haunt Johnny to appear. It was somehow summoned, and began to wreak havoc in Johnny's household.

Sonic Genesis
The Tails Doll possessed a Sonic hat owned by Johnny, which he used to force Johnny to review Sonic Genesis. Elliott also revealed that the Sonic hat had tried to possess him before the events of the Sonic Genesis review.

Sonic R
His real form first appeared in Johnny's Sonic R review, where it constantly shown signs of negative aggression fueled by the insulting rants Johnny threw at him. At the end of the review, the Tails Doll, angered by Johnny's disapproval of the character, proceeded to attempt to kill Johnny. However, just as it was finishing Johnny off, both Elliot (and briefly, Mark) joined the fray, seemingly destroying the Tails Doll.

SAW The Videogame
Posing as Jigsaw, the Tails Doll trapped Johnny and Elliot, before forcing them to play SAW: the Video Game. When Johnny and Elliot gave it a miserable review, they questioned the identity of Jigsaw, who turned out to be the Tails Doll. Johnny and Elliot free themselves and prepare to face off with their nemesis once more. Before a battle can ensue however, Mark entered the scene, despite the warnings made by Johnny. Mark then turned the TV off, locking the Tails Doll, seemingly trapping him for eternity.

Mega Man 7 and Ghosts N' Goblins
In Johnny's Mega Man Marathon, the Tails Doll had actually found refuge inside the residence of Nathan. There, Nathan humorously titled it "Demonic looking Fox Thing". Later down the road, When Johnny commands Nathan to leave, Nathan warns Johnny that the Tails Doll had disappeared in a flash of light, laughing maniacally. We then see a close up of it's mug, and it continued to make cameos in Mega Man 7's credits, and Mega Man & Bass. However, we wouldn't get a clear look at Johnny's old arch nemesis until the end of Mega Man 9/10, where after luring Johnny to play Ghosts N' Goblins and Super Ghouls N' Ghosts, Tails Doll warped behind Johnny, taking the reviewer by surprise. Tails Doll then made Johnny review both games.

During the events of Johnny vs Ghosts n' Goblins, the Tails Doll seemed to have gained sanity and a sense of honor during his long exile. He seems calm and collected, and did not seem to care to help Johnny skip the later half of Ghosts n' Goblins, though mostly because he also disliked it. When Johnny finally conquered both games, the Tails Doll seemed to have grown a mutual respect for Johnny, and seemingly Elliot (though he still requested Mark to suck it). Near the end of the review, the Tails Doll calmly foretold a final battle of bad games, although it was unclear which one it was. However it seems he left a clue; as Johnny proceeded to smash the NES cartridge, the Sonic Hat is seen observing Johnny from a distance.

Donater' s Marathon
The Tails Doll appears again at the end of the Psychonauts review, stating that he should probably have taken the rest of the games out of the box. After the Megaman Network Transmission review, Johnny pulled the next game from the box... Ecco the Dolphin. During the EtD review, Tails Doll is shown to leave messages for Johnny, showing that this is the game he promised Johnny would play to drive him to insanity.

Alternate Forms
Tails Doll occasionally takes on the form of others to deceive them.

Sonic Hat: Tails Doll first appeared to the brothers while possessing a sonic hat. In this form, He was able to possess Johnny and forcing him to like playing Sonic Genesis. John eventually destroyed it with Elliot's help. In their fight John figured out Tails Doll was possessing it, to which Tails Doll confirmed.

Jigsaw: Tails Doll would later pretend to be Jigsaw and force them to play SAW the video game. He would later be trapped in the TV for 3 years as a result.

Trivia

 * Tails Doll is a character from Sonic R.