Thanks. It was a duplicate issue. I thought I deleted the whole Unity Ads package from the asset store but some things were still left in the plug-ins folder.
Yeah. I'm just making sure everything works with 2 enemies so i can see if there will be problems. I just found a new solution for the player homing in on an enemy different than what you see in the video.
The build fails at the very end of loading and gives me this line:linker command failed with exit code 1 (use -v to see invocation). All i have is an empty object which contains the FSM for the actions UnityAds is Ready and UnityAds Show Ad.