You sure they're dead?
((Also, the universe as made by some stuck-up pretentious type and then messed with by some random jerk, heh.))
See if there's anything salvageable from what little remains of the hoomans and their civilization.
Yup, they're pretty dead. The world itself is salvageable though, and there are a few survivors.
Be interesting. Pull out a draft copy of the World before they killed themselves, and drag a sizeable population to continue living in what's already broken. You've learned during your time WAITING that your experiments have created for themselves tools to increase their efficiency. They will live on.
You kept a few notes on your world, not enough to recreate it, but enough for a framework. You drag what's usable and keep it aloft by rewriting some of the physics. The hoomans themselves seem to adapt to their new world by using a loophole in your shoddy physics laws - thaumaturgy.
Well hey, it's not like those hoomans were a great idea anyway. I mean, nuclear Holocaust? Silly hoomans. Since you're so pressed for time though, maybe you can just reuse some stuff from their Universe to save some time. Those "solar Systems" they were living in where pretty dope. Gotta say though, they would've been way better if they were inhabited by... Giant Space Whales! Yeah, those'll get you a good mark.
Take a Solar System and put some Giant Space Whales in it.
And give them an enemy- the feared Space Kraken!
The new world will need to settle for a bit. In the meantime, you have a great idea.
Space whales!
They feed on astral energy and pollinate worlds with life, creating a galactic ecosystem. But no ecosystem would be complete or stable without a predator to keep the whales in check. What you need are....
Space krakens!
Now you need the piece de resistance to top it all off!