I've encountered this three times with different people. [b]First Time[/b] Doing the archive mission with a friend. He was very much alive and killing enemies, but appeared to be cloaked. My screen kept saying "last guardian standing" even though he was alive (but invisible). When we went to activate a switch, he started to punch me (just to tease) and it killed me. After that, he could not revive me because he was "dead". [b]Second Time[/b] Random mission... can't remember which one, but with a different friend. This time I was invisible to her. For testing, I killed her with a fusion rifle and could not revive her. I had to kill myself with a rocket launcher so we'd both respawn. [b]Third Time[/b] Farming glimmer with a friend in the exclusion zone (neither of the people playing with above). He kept asking "where are you?" because I was invisible and it kept saying last guardian standing. I asked if I was invisible. He confirmed. Blew myself up with a rocket launcher so he could revive. I was no longer invisible. All three instances were PS3. I have no idea if this happens on other platforms, but it's happened three times that I know of in the past month. Last incident was yesterday. If it happens to me on PS4, I'll upload video. Has anyone else encountered this?