I would go with invisibility. Time travel can mess stuff up.
EDIT: I'm glad this is back. Many memories in this thread.
-
Edited by GiantDad: 3/6/2014 5:00:22 AMTime Travel, it's truly my one desire in life. And for everyone who thinks that it messes stuff up, the paradoxes resolve themselves unless it's a fixed point in time. #DoctorWhoNoseEverything