ninjas are fast, deadly, have cool weapons (everyone wants a katana its on everyones top 50 things to have list), and being called ninja is a compliment cause thats how cool they are (whats up mah ninja) unicorns are also fast, can be deadly (unicorns on drugs), they are horses with horns ( you know if you had a horse it would be 50x better with a pointy horn, and they shoot rainbows and sunshine all over the place, and they are frickin mythical beasts of epicness WHO WHOULD WIN ANSWER THY QUESTION PEOPLE
I like unicorns.. sorry, i'm a girl, can't help it haha
they look so nice! and i'd love to ride on them, guess it would probably be the same as horseriding, only that you don't have to fall on it's head hehe... that would be pretty painful:P
Meh. There are so many different powers attributed to unicorns and ninjas that it would be very hard to discern who would be the victor, and of course we have our hardcore ninja and unicorn lovers.
On the side of ninjas, they have their super speediness and awesome weapons, only needing to stand at a distance while whirling ninja stars at the hapless unicorn. Even if it came to close contact, they have the famous ninja sword thingy.
For unicorns, they have their horn, and the generic idea of wingless flight. They could avoid the ninja stars and keep up with a ninja's super jumping ability, and against the ninja sword would come the horn of justice. Unfortunately their speed could not match with a ninja's.
In the end, a ninja has to much flexibility, and even if a unicorn could overwhelm one with it's strength and valor, a ninja would be quick enough to come out the victor.