well since people can use console commands to spawn whatever they want and bring it from another game into yours, and adjust their skill levels to any level with the console commands, without you knowing about it. I'd be seriously weary of multiplayer with strangers. There are tons of people willing to ruin the natural progression of things. I'd strongly recommend not playing with more than 2 or 3 strangers if you don't have your own group, becomes very hard to keep track of what's going on and if they are somewhere else in the world as it is large enough to accomodate many others, well I just don't see the point if you are not going to interact with eachother and go your own way instead...