So, in Andvari Bio Lap on Esamir I stumbled upon said Infiltrator that was someone getting up to the ledge of the outside walkway part of the building that A point is on. I'd ocassionally shoot where he usually appeared and go no hits, and didn't see him. But sure enough he'd appear stealthed and kill me. He appeared up a tree on the opposide side. He then somehow got on to the roof of the building A point is in. I'm just curious how he got there, or any of these places. I'd assume you'd need a jetpack but you might not. He also immediately messaged me after i managed to kill him on top of the building because a turret turned to him and i became aware not to trust high places with him around.