Ghost Class Mutant?

What are those and why did 3 lvl150 Ghost spawn out of nowhere and wiped my whole team?
They had a “C” where the class icon was and only had 1HP.

they are use for some players ,
who use automatically fight program .
if you meeting them again ,
please press □ button ,
shutdown game progress and re-login again .

What do you mean ghost class mutant?

3 enemy tanks whit only 1 HP ,
but them can fire 6 times to you .