Mick. At first glance he looks like just another thug who can't go more than 5 minutes without grunting. But, when Sara, Constantine, Nate and Leo were stuck in that mental asylum Mick took over and in 3 seconds told everyone what to do. He's a celebrated author, so his lenguage skills definetly go further than he usually lets on, and with the time he spent with the time masters, and with the Legends, I'm sure he knows more about time travel than most people think.