The stretch goals will make the Darkness a playable faction for a player, but the Darkness will also be an AI for solo mode. The Prime Shadow monster was an early backer exclusive that they made available as an add-on.
The terrain is not necessary. It will offer only minimal differences in gameplay. The terrain and boss expansions are in resin and are intended more for hobbyists who want to model and paint. They have the full-color cardboard standees available for much, much cheaper if you're interested in picking up any bosses or terrain.
Ok. I just read the last update. So if I back the faction level. I'll get two playable factions (1 being an AI controlled as well). I guess the bells isn't a boss model in size like the other bosses that are £60 nor operates as such. So there isn't a free big boss. Ok. I'm starting to piece this together.
Eh, this makes the faction pledge more enticing at least. $55 for two playable factions isn't bad actually.
However if this is a playable faction, and the prime shadow monster is an add-on...how does that factor into it being a playable faction. I assume I don't need it to have a equal set to the faction I end up getting?
Edit: Eh...they haven't unlocked the playable faction. No go I guess.