Good thing with games like this is they're always there and you can easily jump in and out of them when you fancy. Hard to do the same with SP games without ruining the flow of a story.
Here's the launch trailer from PGW:
"My name is Ozymandias, King of Kings:
Look on my works, ye mighty, and despair!"
Nothing beside remains. Round the decay
Of that colossal wreck, boundless and bare,
The lone and level sands stretch far away.