People's descriptions are always awful. This narrows it down to half the map.....let me help you... Do The Last Array mission in Skywatch, follow the waypoints through the building, through that room where you fought the wizard at the very beginning of the game. Follow the waypoints until you come out of the building, then straight ahead to your left is a field. There will probably be some pepole there shooting into a cave. Right below the building on top of the hill, you will see a cave entrance, to the right of the big downed spaceship. Just shoot the enemies as they come out of the cave and then go into the cave when you run out of ammo to collect. But NOTE: 1. Stay BEHIND the fallen pillar and more enemies wil come out. If you are too close, you get only 3 hive. 2. All the enemies that come out of the cave go fight the fallen in a field to the right, on top of the hill, the hive all have to be dead for them to spawn from the cave.

Oh and on #2 do you mean fallen need to be dead?

Old Russia, cosmodrome. Where the hive and fallen are fighting trust me you'll like 5 people farming there already

Is it that known to were people will already be there?