I'm level 5 in everything in BA. Def is hard at first but super easy once you get the hang of it. What I do is fill my inventory with bait at the beginning and then drop bait (any kind of bait, does not matter if its the wrong kind) every 2-3 squares from the cave exit towards the traps on the right side. I then collect 2 logs at the top and circle back around to the bait machine, get more bait, and basically keep dropping bait from the runner exit towards the traps. Then I drop a bunch of the CORRECT bait right on top of the traps and wait. The runners will be lured towards the bait (and away from the exit) even if its the wrong kind, so as long as there's a steady stream of bait leading from their exit towards the traps, none will get through. The only reason def is any harder than the other roles is because you have to be constantly moving, repairing traps and laying down bait. If you know what to do though you can't fail.
