Looks like the invasion mode (Empowered Demons, which you can turn off or on) isn't making it to launch? Kind of bummed as that's the time this feature would be the most fun and accessible. It sounded pretty neat to be able to be a demon and invade someone's game. Hope it makes it soon, in fact they could really expand on it if they wanted and it was a popular enough feature. Maybe the 2v1 battle mode will suffice. I don't know why I even give a shit about any sort of MP, as I mainly care about the SP, but I guess I just want the whole package to be godlike.
Or maybe I'm full of shit? (taken from the doom wiki)
Occasionally an "
empowered demon" may appear in a player's single-player campaign, bearing the name of a player that was killed by that demon in their own play session. Such demons are stronger than normal, but give special rewards when defeated. Empowered demons are strictly optional.