In my opinion, there's no point in doing this in Heroes because:
1. Heroes is already almost a game over after the first kill of the main hero.
2. If the zone is in the middle, it will be very easy... by the time you explore the map.
3. I see the development of the idea only in one direction:
A limit is given for a month or two.
and the battle goes like this: several heroes are released at once.
and battles take place between small heroes...
and if you develop them into big heroes, how is it different from the usual game at the moment?