Disclaimer: Not mine.
Reno: Climbing the Ladder
None of the Turks were very happy with their order to drop the plate on Sector Seven. Just because they were ruthless corporate spies and hitmen didn't mean they were murderous thugs, or so they liked to think. They had their concerns for human life.
It was an open secret among the Turks that Tseng had a bit of a soft spot for Aeris. The order to bring her in was obviously causing him some difficulties, though his professionalism would always see him through.
Rude, too, seemed to be worried about something, or someone. Reno had no idea what that was about.
In the end, Reno volunteered to be the one to ensure the plate fell. Tseng's cool efficiency was starting to crack under his concern for the Ancient. Rude, though he never said so, was hesitant.
Reno, however, had no such emotional attatchments or qualms.
He'd been born and raised in Midgar. He was a survivor. The poor of Midgar had to be. But unlike many others, he had climbed out of the stinking slums, to the plate above. Tseng had handed down the ladder. He realised that the price for the help may well have been his soul, but he had no use for it anyway.
He owed Midgar nothing, and his colleagues everything. So he was the one to fight AVALANCE and commit mass murder.