Board Thread:Versus Debates/@comment-34436445-20180528184455/@comment-9782468-20180529224345

Namikazenaruto9 wrote: Just because it uses chakra doesn't mean he can see right? After all Kakashi couldn't see past Hidden Mist Jutsu. The reason Kakashi can't see past Hidden Mist is because Hidden Mist is chakra-based. His Sharingan gives colour to chakra. If it were regular mist, he could see through it.

As to how that affects whether or not Itachi could find Muu, idk. Someone said he can even erase his chakra signature, which I'm a little too lazy to go fact check. If it's true though, then Itachi wouldn't be able to see him because there has to be chakra to see. If Muu wasn't erasing himself and just hid behind a rock, then Itachi would be able to see his chakra through the rock.