Running Functions about Players?

One thing you could do is use a while loop and check the number of players:

local lobbytime = yourintermissionlength
local play = false

while true do
	if game.Players.NumPlayers >= 2 then
		if play == false then
			wait(lobbytime)
			play = true
		else
			--your code
			play = false
		end
	end
end

The way I would prefer would be something like this

repeat wait() until game.Players.NumPlayers >= 2

function game()
	game.Players.PlayerRemoving:connect(function(plr)
		if plr == your_it_or_something or game.Players.NumPlayers < 2 then
			return nil --(or something else you want to put to stop the function)
		end
	end)
	--game code
end

game()

your_it_or_something is what I put for a conditional statement checking if the player was the seeker. Depending on how you track the seeker, you can change this statement. If you can tell me how you keep track of who is "it" then I can help you replace that bit. Here are some basic things:

-if the seeker's NAME is stored in a local variable, change the line to

if plr.Name == seekervariable then --seekervariable would be your local seeker tracking variable

-if the seeker's PLAYER is stored in a local variable, change the line to

if plr == seekervariable then --seekervariable would be your local seeker tracking variable

Once again, it would help if I could know how you store it.