It's a fantasy role-playing game.

DM: You are Mollymauk Tealeaf, a tiefling blood hunter . You are the member of the famous group of adventurers. Previously, Caleb grapples it with Earthen Grasp. It manages to clean the tar off the lens, and breaks Caleb's concentration on the grapple by pinning him against the wall with a blade through the chest.
DM: All right, there you go. You can still keep it in your visual range, but that’s 30 feet back. Now you spin around with your crossbow, not suffering any attack of opportunity. All right, Molly.
Player: Can I see anywhere where there seems to be a crack in the armor and make a--
DM: You may, yes. Well, you can try and inspect.
Player: I want to see if there’s anything that looks like a good target to start doing some damage to.
DM: At the moment, it hasn’t taken a lot of damage, and it’s hard to see if any--
Player: Is there a plate open or anything at the moment near me?
DM: The only plate that’s open is the one that has the lens visible, but it’s really close to the body and right now there’s blades spinning in its space.
Player: I’m going to try and get to the side without the blade. I’m going to try and chop open one of the plates on the back. I’m going to start hacking away at it. Actually, even with the blades, there’s an open place right now? Is there a place for me to start poking the tender insides?
DM: At the moment, not really. It’s still fresh in battle, and its armor plates are pretty much protecting all of it.
Player: I’m going to try and find one armor plate and start going to town.
DM: Where are you going to attack its construction?
Player: I want to get to its left hind quarters. I’m going to run over to the opposite side, flank it with the lollipop.
DM: Oh, with the lollipop? All righty. You’re going to be right there, on top of the door?
Player: Mm-hmm.
DM: All righty, take your attacks.
Player: First attack is a natural 20!
DM: Nice! Make your damage on that and roll the second attack. That’s--
Player: 2d6 with ice damage. That’s (counting) 17 points of damage.
DM: 17 points of damage. Nice!
Player: Next attack with the same sword. Actually, I’m so sorry, that’s the wrong sword. That’s 18 points of damage because of the Summer’s Dance.
DM: Correct.
Player: Then the next one, Summer’s Dance again, is not quite as good, 12. That does not hit.
DM: 12 does not, but first strike carves through and some of the armor bends inward. As you cut through, plates bend inward, and have to try and retract to protect, but they’re locked in place. You’ve actually bent them to the point where they cannot reform this armored mesh. It’s trying to correct itself, but busted in place. The second strike, as you come down, one of the blades catches and parries it off to the side. No impact on the second blow.
Player: Okay. Going for a third strike.
DM: Go for it.
Player: 14.
DM: 14 does not hit. This is a tough mother. You go to strike a third time. You do hit, but it just doesn’t cut through. The blade shakes a bit. You pull back, cursing yourself.
Player: Is it worth seeing if it’s going to-- well, it’s blinded, so it’s got disadvantage if it tries to even hit me with an attack, so I’m going to try and back off and climb up that little hill.
DM: For those questioning, even though it is blinded, it lowers its attack, because some people are like, "Attacking things with blindness have advantage!". Because it is nothing but a spinning, whirring of blades, and technically it has multiple forms of sight, it is not granting advantage on the attacks against it.
