Imagine strolling though Cyrodiil, your trusty sword on your belt, your bow on your back. A stream gurgles quietly just past a beautiful field of lush, verdant grass. The birds sing loudly and merrily from the tops of trees.

You walk into Frostcrag Spire, through the great hall and up the ramps to your spellmaking altar. After a bit of study and experimentation, you create a completely new spell! You head back out and down the nearby city of Bruma to test your Speed Up Time spell.

As you mutter the incantation and wave your arms about dramatically, everyone around you yelps in shock. Their swords have become combat knives. Their maces have changed into baseball bats. Their bows are now assult rifles. What's going on? Your see something large and bulbous whizzing through the air towards the Imperial City, then with a flash that quite literally destroys your eyes and roar of noise that tears into your ears you're dead.

Anyways, free-roam post-apocolyptic game. Not Oblivion.