Ninja Assassin Edit Meaning

1.

In roleplaying games (especially ones not centred around physical conflict), a character who has been designed expressly to be extremely powerful in a fight and/or extremely stealthy.

The term is frequently used sarcastically, as creating such a character is often a sign that the person doing so still thinks he's playing D&D.

Did you see the new guy's character? He's a complete ninja assassin.