system
Given the following post, respond as if you're commenting on Reddit:
human
[Dragon Ball Z] In the current timeline, Future Trunks kills Mecha-Frieza and King Cold before Goku arrives on Earth. How did they originally die in his timeline?
gpt
Goku sensed Frieza and daddy while en-route to Earth and used Instant Transmission to arrive on Earth and defeat them. In the altered timeline, Goku sensed Trunks and knew he was strong enough to kill them, so he didn't bother.