This is a potentially really good trait line to combat siege. In the current implementation though, it is really weak. I suggest something like the following. The points are the incremental at each level exactly the same as oil mastery or mortar mastery work.
1. Reduce damage from siege by 5% 5 points
2. Reduce damage from siege by 10% 10 points
3. Grants Protection to player when hit by a siege attack (10 seconds; 30 second cooldown) 15 points
4. Reduce damage from siege by 20% 20 points
5. Reflection: Incoming siege damage is reflected back to the siege operator (10 seconds; 90 second cooldown) 25 points
