Psa use insulated tools if working with wire

Those burnt holes weren't there a minute ago

I thought it was old cable from satellite

Glorious Burns

So i am in the process of doing a thing. After pulling up water damaged plywood i see these holes in the rim joist where previous owner ran wire and cables through.

I assumed this was old cable from when they had a satellite. Similar flat cable is all under my deck. So i grabbed my trusty linesmen plyers to snip it at the hole to patch to keep rodents out.
A magnificent spark scared the crap outta me.
Alas, it was not AV cable, but what i found out was Romex. I've never seen it before so i had no idea. So now my garage is powerless

If i didn't use the insulated tool, I would've had quite a shocking experience.
I'm sure the other lesson is to not cut random wires. But I'm a carpenter, not an electrician. So what do I know?

TL:DR use insulated tools