Transformers Optimus Prime Vol 4 Author:John Barber Darkness falls over Cybertron as the legendary Onyx Prime returns, throwing the planet into chaos! What does this mean for Optimus Prime--and the Earth? — As Onyx and his comrades sow panic and dissension on Cybertron, Windblade defends an already tense planet against a secret that could shatter it forever, Soundwave questions a fragile alliance,... more » and Optimus confronts a mystery that goes back millions of years.
Collects Transformers: Optimus Prime issues #15-21.« less