The newest features though are the hero/dark bars and the inclusion of weapons

As for the dark/hero bars, this feature works somewhat like this

If you attack humans/good people, your dark bar goes up, and if you attack villains, your hero bar goes up

They both top up as you do associated deeds

You can choose to try and go through the levels as fast as you can, or complete the missions that are offered to you (from destroying one escaping airplane to slaying 50 aliens)

From the beginning of the game I was confused as to what my objective was