One of Cybertron's refugees who fled the planet to avoid its certain destruction, Callback eventually took the form of a pay phone along a stretch of lonely desert highway. Fortunately, he had a buddy who placed himself across the road.
Unicron Continuity (Animated)
- Actor: Terry Klassen (U.S.), ??? (Japanese)
After a final conversation, he watched his friend Signal Lancer run off to find his destiny among the stars, wishing him luck in accomplishing his desire.
- This character is unnamed in both the original and English versions of Cybertron; To that end, the fan-coined name Callback is used.