Currently, the Mantis Blades are horribly bugged in my game. I'm not sure where or when the bug occurred but I noticed it after doing some stealth kills and stashing bodies, so I'm not sure if this was the trigger. Either way, as you can see the most noticeable part of the glitch is that one of V's finger nails detaches and floats near your hand. There's also a lot of visual jerking going on when the blades are out and it's all together pretty janky. Moreover, the wires and other intricacies...

Mantis Blades visual glitch