The Tails Doll (Te-Ru Doru in Japenese, and also is mistakenly called Puppet Tails or Tails Puppet) is a robot / doll version. He is comparable to Tails in the same way that Metal Sonic is comparable to Sonic. Tails Doll has a metal rod coming protruding out of the top of its head leading to a red gem that seems to control the creature's movements. Tails Doll is a secret character in the game Sonic R, unlocked by finding the 5 tokens in the "Radical City" track and finishing 1st, 2nd, or 3rd in the race. Tails Doll has poor handling, average acceleration and average top speed. Its jumping abilities are quirky; it cannot jump very high, but seems able to float. It is also the only character who can float over the water without slowing down after a period of time.
- Tails Doll seems to be one of Dr. Robotnik's creations. Sonic R features metal versions of Sonic and Knuckles. However, in place of a "Metal Tails", there is Tails Doll, an unusual move. Tails Doll was most likely created by Traveller's Tales, the team that worked on Sonic R but not on any other Sonic games. This likely explains why he has not yet appeared in another Sonic game. Although similar-looking dolls appear along with Sonic dolls and Knuckles dolls in Sonic Adventure DX: Director's Cut as targets in E-102's first level, these Tails dolls do not have red jewels.
- Tails Doll has a small following among Sonic fans due to its supposed "creepy" look in comparison to the other robotic counterparts in the game, Metal Sonic and Metal Knuckles. In many fanfiction projects, Tails Doll is supposedly able to materialize and slaughter, possess, enslave, or suck out the souls of those who complete Sonic R or tag Super Sonic as Tails Doll witch is not true.