If you go into the menu and select Solo Campaign in Back 4 Blood, you’ll see a scary message:
Uses solo decks created in the Fort Hope deck menu. Maps and objectives will be adjusted. Matchmaking and player invites are disabled. Earning Supply Points is disabled. Stat tracking is disabled. Earning progress towards Accomplishments is disabled.
All of that sounds very punishing, like Turtle Rock Studios would really rather you not experience its game this way. But a solo campaign is actually a great sandbox mode for people who want to try new things or play at their own pace.
Back 4 Blood gives players a card system that impacts stats and some abilities during a run. Normally, players need to use Supply Points to unlock these cards. But for solo decks, all the cards are immediately unlocked in the menu. There’s no buying required; you just build the deck you want and go.
With that context, the rest of the restrictions start to make sense. Supply Points are for unlocking cards, and you don’t need those when you already have them all — plus, Turtle Rock probably doesn’t want players endlessly farming points with bots, which would trivialize the in-game economy (you can’t buy cards with real money).
Because solo instances are different, it also makes sense not to allow invites. And Accomplishments — Back 4 Blood’s name for achievements — may be easier or even exploitable with fully upgraded decks and bots, undervaluing some of the rewards they come with.
During my review session, I played the first four levels of Back 4 Blood with bots. My biggest issue was their general stupidity on the Recruit difficulty, and their inability to accomplish main story objectives or mount turrets. But, in a way, I had more agency over my playtime. It was a calmer apocalypse most of the time, where I wasn’t rushing to keep up with internet randos or waiting for slowpokes to figure out what to do.
Back 4 Blood is certainly more fun with real players, and probably even better with a group of friends shooting the shit. But it’s not an awful solo experience. And with the increased mission variety in Back 4 Blood, solo players who just want to see all the levels should have a fine time dragging some AI with them through the zombie horde.