Don’t use a rock, you just need a piece of wire, a string orca piece of shifter cable...
So last week I wanted to take off my chain, give it a thorough cleaning, and remove two links. Not having quick link pliers, I first tried an old shoelace. Then I tried some old climbing cord. Then I used a section of cable. It had always worked before on my cross bike, but after cutting into my hands there was no movement on the quick link. I was just about to order a set of pliers, but went down to try it one more time. That's when I noticed my "quick link" is actually a master link with the retaining clip.
I am an idiot.