I’m in a similar boat with BO2 and BO3 Zombies. Except in my case, it’s because I don’t have any friends even remotely interested in the game anymore. And holy shit is training a group of zombies in circles for hours boring when you’re alone. It’s a shame because I do really like the early game setup still. Buying perks, finding and upgrading weapons, and opening up the map. Especially on high quality custom maps I’ve never explored before.

I still find easter eggs fun to do, but most require a group which completely kills my chances of doing them. Origins is my favorite vanilla map though, and at least that one can be completed solo.