9.5
It's everything the first was plus plenty more. Add in some friends, and the game is literally unlimited in its replayability. I've spent countless hours in both games just messing around with friends, not even trying to complete levels. You can't get more fun than that.
However, it's a bit too "epic" for its own good. I found myself getting somewhat frustrated by the constant cutscenes during the story mode, and friends who were new to the game would say things like, "Can we just get back to the game? What the hell is even going on?" Nothing like that happened with the first. It's Super Smash Bros. Brawl syndrome, only worse. Simplicity is key for a game like this.
And I believe this is the first game I've bothered to rate in one of these things lol.