This was definitely the roughest of the Heist challenges, and maybe the hardest combat challenge so far... hard to be sure unless I try a No Upgrade Run of it, but... that doesn't feel very likely right now. This challenge has both a heavy thug and a whip enemy, which can make for a real problem, especially if you don't notice them in time. Other than that, focusing on getting the Photobomb kills makes it difficult to play well, especially with the cutscenes interrupting you constantly. But you can't get enough points to get the three star without them. It's also difficult to focus on everything else you need to be managing while playing fast enough to get the full 25000 points from the time bonus. I think this could still be done no upgrades, but it's going to take a lot of concentration and execution. You're really got to be diligent about your gadget execution. Here I'm relying on Scavenger to net me plenty of extra Trip Mines to make things go smoothly. The one saving grace of this mission is that it gives you at least three electric panels to help out, so I think if you used those intelligently, they could make a big difference when doing it without upgrades and having fewer gadgets to work with.