[ Mercenary, solider - there isn't all that big of a difference, as far as Cisco's concerned. Not categorically. It doesn't change the fact that Taako had killed people in pursuit of the goal - to save the world and keep his friends safe and that sort of shit. And it's useful to know, just in case they ever do come to that eventuality, and Eobard Thawne shows up. Because Cisco's pretty sure that a man as dangerous as him shouldn't really be locked up, and it's good to know there's at least one person he knows who could probably do the deed without a serious moral crisis. ]

I haven't. Just... while we're sharing.

[ He doesn't say it like he thinks he's better than Taako, or worse than him - just not something they've got in common. If push came to shove, Cisco doesn't know if he'd be able to do it. Maybe to save a friend's life. Or maybe not. ]

I mean... I thought I had, once. When the particle accelerator was about to blow, my friend Ronnie went in to fix it and said if he wasn't back in two minutes I had to lock him in, and I did. I thought he was dead for like a year, but it turns out he just fused with this other dude and got thermonuclear powers, so it all worked out in the end.

[ Which Cisco knows isn't really the same kind of killing Taako was talking about, but it's the closest he's come. ]