What to dress up for Halloween?

I need suggestions on what to wear for the incoming Halloween. Two years ago, I dressed up as Asami Sato of Legend of Korra and last year I was Commander Lexa of The 100. I was wondering what’s a good costume for this year. I need to look dress my best because our company HR said the best costume gets to win free tour to our local destination of choice. Any suggestions from you guys?