The exodii serve a number of roles. The first is that they’re just fun: they’re strange interdimensional scavenger-survivors. What’s not cool about that?
From a game design perspective they offer the following:
- add world building by showing that not all dimensional travellers are overtly hostile.
- also add a source of lore regarding how the apocalypse plays out and some of the backstory that would be almost impossible to add any other way.
- lets us reinstate several categories of monster that, if they originated on cdda-earth, require cdda earth to have been far more unfamiliar than I’d like. Exodii quadrupeds fill a similar niche to tripods and beagle tanks, without wondering why the hell America would field such an overly dangerous and stupid thing and yet otherwise be similar to our world.
- removes most of the requirements for cbms to make sense, allowing us to stop the cycle of either removing fun but silly stuff or having to create really bizarre lore explaining why there are shotgun arms
- makes it possible to have a new way to get cbms that’s far less random and contains some new play elements distinct from just randomly looting them like you did with everything else
- makes it feasible to have far more weird and extensive cbms than before, like a full body conversion.
It’s also important to understand that they’re not friendly aliens. They’re not really friendly (just not hostile), and they’re human. People keep thinking these are UFO flying green men. They’re much more like your survivor than anything else.