So this is not set in stone, but this is the build I use most of the time. This build allows me to be able to do high siege damage and hero damage as well. First talent is kind of a personal preference I would say, but I like the extra damage at further range since I am usually at the back of team fights and out of range of turrets taking them down. Extra range is never a bad thing for the second talent. I like to have extra survivability so I go with first aid. I like napalm strike better than blunt force gun, but it's probably personal preference you can try it and see how you like it but napalm strike has a very short cooldown and kills really well from what i've seen. I like giant killer next best, because first strike only works well if you haven't been attacked and I always get focused. Graduating range or stoneskin depends on if you feel like you need more survivability or range. Nexus frenzy is what makes my build good for siege damage. Sgt. Hammer already does good siege damage and this just adds to it. Use this and have fun!