In case you haven't found out already, warlord's geo-mods potential is
amazing. Here is just an example: go to the top of one of the towers. On
the left side of the top, blow a hole. It's always good to a human
player helping you who will follow you with his rail gun so you don't
get lost in the cliff. Dig at a 50 grade angle (45 degree) until you get
to the top of the cliff. Do not go above the top or else it will get all
glitchy and messed up. From here, you can snipe down with your rail gun
or sniper rifle on anyone on the map.

Also try digging a trench between the 2 bases. You can dig tunnels, too.
It's amazing what a few geo-mods can produce.