Playing Assassin's Creed: Revelations for the third time on PC. Having a bit of problem. Played 9 hours so far, capture all Templar Dens except 2 to go yet. There's a challenge on Assassin's Guild that says "Successfully perform a Den Defense 1/3" which means I defend it only once where I have to defend it 3 times. But the problem is Templars aren't attacking my dens so I can't complete this den defense challenge. Templars attacked only once. I have recruited 9 Assassin's so far. And four of them are assigned as Master Assassin on four different dens. Anyone knows how I provoke Templars to attack my den?