What if your #battleroyale game is on an infinite, procedurally generated road? You can control the length (between zombies and the military, or “blue” and “orange”, or whatever), so you don’t need 100 players to start. You can split and merge roads (servers). Throw in some random events (floods, herds of animals). You can adjust how people spawn (from the “alleys”). Perhaps new players are the only source of loot (you spawn with a gun, ammo, and a health item – get more/different from others).