[2.2.13] Enemy Distance(?) is possibility broken at high distances.
Prob just like how the Attraction Shield Bug (#1045 (closed)) occurs where you were able to pull in Rings or Homing Attack enemies from far, FAR away. Enemies appear to be affected by this as well.
In this video is a heavily gutted Deep Sea Zone 1 map, though I also moved it somewhat close to the top of the block map. I threw in some sectors around the center point and marked down some textures to keep track of things.
Splitscreen was used to show two viewpoints. Player 1 enters a tunnel to enter the Brak Area while Player 2 is behind a raised missing texture wall just so the Dragon Bomber doesn't aggro. When Player 1 enters the blue sector area... the mines will "see" Player 1 and then go boom which you can see on Player 2's screen. Messing around further the Dragon Bomber will then aggro since apparently it "saw' Player 1.
One other thing to note is that the sound effects bugs out when the distance between players is so great that it either won't play the sounds or it'll play for a few frames and then give up. Could be a splitscreen thing but it might also happen in Multiplayer?
Later on... I placed two Cyberbrak bosses in the area where the Mines & Dragon Bomber is at and... well... they "saw" me as well which led me to believe that whatever distance check they're using just ends up breaking... or maybe the map cords bug out hence why they can "see" the player. Not exactly sure.
Here's the map image. (Click details to view it)
Here is the map. Replaces DSZ1 (Map07).