Requiring a certain player be in the game

I was just wondering, is it possible to make a map check for a certain player name in all of the slots, and if that player isn't present in the game it will end the mission in defeat for all players?

Thanks

Yes

its a condition... player slot status i believe its called

Even if the game required you to be in it to be playable, noone would play with you still. Give up already. =)