Well. I don't know what we're saving the world FROM. but that seems like a good place to start.

Maybe they can fight off hunters? For more actiony stuff if ppl want that?

Maybe the volunteers weren't the first ones? Players have to defend themselves from failed genetic experiments?

And yeah, nailing down what the big threat is, and why giving volunteers animal DNA is the key to combating it is probably the first thing you want to do.

The big threat at the start is ecological collapse, but as things progress new threats will appear, more solid threats, perhaps even linked to the first situation's roots. Though poachers and failed experiments are a grand idea, and I know why they did the things they did.

Some events that might also allow for other transformations to 'experiment' with, perhaps; on another, fields and things that force the characters to hunt, sometimes like actual animals, though that could be more of a setting thing; on a sillier one... having them for a pet cafe.

Hahaha.

They will be able to get that as a job, more than likely.

Ah! On another one... I think the characters would also be incredibly well-suited for exploration of new territories. They'd be more sensible to the changes in environment, and be able to locate water and food.

That was part of the intention!

They will be exploring mostly areas deemed uninhabitable by past generations alongside NPCs, to check for recovery.

Chernobyl exclusion zone type areas?

The "place that's kind of retaken by nature but a lot of the signs of life are just kind of There abandoned"

/human life

Yeah! Some might even be irradiated, but there will be warnings.