That the island that hasn’t been unlocked yet is where the Apple Murderer (hopefully serial killer) likes to hunt. All the off-road vehicles have been disabled by him (add a mission where you have to fix them to be able to use them to get to locations that are impossible by foot), and we the players find new kinds of fireworks that he created that sorta hypnotize whomever, or WHATEVER is unlucky enough to come across. As we follow numerous clues to catch him, booby traps become more frequent and more deadly, all the while faster and meaner upgraded machines are devising better strategies that require smarter tactics and better distractions from the player to survive.
I’d play that. Sounds like a fun idea