Do not slander a slave to his master, Or he will curse you and you will be found guilty.
It is very tempting when you are dealing with a narcissist co-worker to “take it to boss”. However, this has a high likelihood of backfiring. In the process you will likely get something wrong – the way you approached it, your attitude, getting one or more facts wrong, etc. The narcissist will typically quickly figure out what you have done wrong, and somehow use that to turn the tables on you.