My idea: Artillery. Not to far off from your HQ there will be artillery machines and the engineers from that side will be able launch artillery shells. The way will be able to launch it will be a pad with the map and your finger will make a circle where you click and that will be where the shell will land. There will be a 1 minute cooldown. If somebody where to call in artillery they would open their menu and below the leaderboard there will be a map and they will click where they want artillery and that will come up on the artillery pad. So that people won't take advantage of it dead people won't be able to call it in.