First attempt at a Rescue Bots fanfic.
Heatwave felt his spark drop the moment he saw the portal close, either trapping Optimus Prime in the past, or somewhere between past and present.
He had been thrilled when he saw his leader come to their rescue. Sure it was embarrassing to actually have to be saved, but Heatwave couldn't complain since he wasn't being ripped apart by Moroco. When Optimus had opened the time machine's portal, Heatwave stayed behind. The humans had been rushing towards them, and Heatwave felt a sense of duty to stand beside his leader and make sure he'd be alright. He also wanted to prove himself to Optimus; maybe then the bot would accept him on the team. However, Optimus was a leader who would place himself in the line of fire first to protect his soldiers. He only had to say Heatwave's name once, using his tone to convey the command behind it. Heatwave couldn't say no to the command, so reluctantly, he entered the portal.
On the other side, Heatwave waited with his teammates for their leader's entrance, watching it close before their very optics. Heatwave felt guilty almost immediately; he should have stayed behind. He should have told Optimus he wouldn't leave a bot behind, ever. His guilt was taken away when the portal reopened and Optimus came jumping out, looking fine. The leader of the Rescue Bots felt at ease knowing his leader was fine.