25th Century Communicator

The 25th Century Communicator is a special event trinket that summons a Pet to aid the Player Character.

Source
The 25th Century Communicator trinket was only given Players with Legendary-level access on December 2012.

Servo
Servo is summoned on activation. It attacks enemies with ranged shots.

Trivia

 * Servo is the first Pet to be able to speak to the player.
 * While attempting to play a game of eye-spy, Servo reveals that he only can see in Cyan.