Yeah that was my problem with the blastoise. It was very difficult to see in the first place, wasn’t on the back and didn’t feel like an indent line at all. I believe its from the factory, I have seen it a few other times on 1st ed base cards.
Again, doesn’t look like an indentation, but rather a dark line running across just the holo of the card. PSA also seems to be of the mindset that it is also not an indent but just a defect with the holo. Unlike OP, my line is angled so there seems to be variation in the defect.
PSA is so weird. You’d have that same line on the back of the card and you’d be lucky to get any grade higher than 6 which I think is stupid, but I also wouldn’t want a 8-9 with that kind of flaw on my holos.
Personal preference, but I actually don’t mind it as you need to have the right angle just to be able to see it. I would rather have the dark line than scratches or whitening.