Assassin 
To dream of being assassinated indicates a situation that has no optimism or chance of success and requires your instant consideration and effort.
To dream that you've witnessed an assassination means that you must pay closer attention to small details. The seemingly inconsequential things are typically important.
Ninja
A ninja in a dream represents unknown intentions. You may be suspicious of those around you or feel threatened by others.
To dream that you are a ninja indicates that you wish to have power over others but are not willing to go through any confrontation.
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