draw the map (make the map rount you are visble)

local radius = 500;
game.player.force.chart(game.player.surface, {
	{game.player.position.x - radius, game.player.position.y - radius},
  {game.player.position.x + radius, game.player.position.y + radius}
})

Destory the enemies nearby player

function () 
	local radius = 250
	local surface=game.player.surface
	local pp = game.player.position
	local cnt = 0
	for key, entity in pairs(surface.find_entities_filtered({force="enemy"})) do
		if entity.position.x > pp.x - radius
			and entity.position.x < pp.x + radius
			and entity.position.y > pp.y - radius
			and entity.position.y < pp.y + radius
		then
			cnt = cnt+1 entity.destroy()
		end
	end
	game.player.print(cnt)
end