In the Breakdown DLC, if I unlock a hero character, but then start a new game, will that hero character ever appear in that game? Or do the heroes only come into play when you unlock them or start with them?
I found this link on the Undead Labs web page with an answer.
A moderator states:
Now, let's add Heroes to the mix. You meet an unlock requirement, gaining access to a Hero.
You finish (or decide to quit) your Breakdown game.
You go to the Breakdown start menu to start a new game of Breakdown. (The unlocked Heroes do not appear in the regular game. Totally separate systems.) Your Hero is now a starting character option, and you can choose to begin the game as him.
But what if you have more than one Hero?
All of the ones you've unlocked, besides the Hero you choose as your starting Hero, go into that pool I mentioned at the beginning. You now have a chance to find those Heroes somewhere on the first level. If you don't find any of them on Level 1, you have a chance to find them on Level 2.
But it's not guaranteed. It's like a goldfish tank at the pet store. After you unlock the big gold one with the swishy tail, he will be in the tank for every subsequent playthrough. But that doesn't mean you're going to get him when you close your eyes and scoop with the net.