Summary: What can I say? This game is totally awesome. I thought Arkham Asylum was amazing, but Arkham City blows it out of the water. This has to be one of the best super hero games ever made. The graphics are amazing, the controls respond quite well, and the storyline keeps your interest. This is one of those games that will cause you to lose sleep because it is hard to put down and you want to keep playing.
Summary: What I couldn't have imagined is that an epilogue DLC to such a great game would be such a letdown. HQR is set after the events of the main game and the basic premise is intriguing - Harley Quinn, mourning for her beloved, manages to kindap Batman himself and Robin must investigate this. However, it doesn't stand up to the expectations - the whole 2-hour experience is bland and adds nothing to the storyline or gameplay - just a bit more convict beating.
Summary: Did you like the main campaign in Arkham City? Yes? Well then, this DLC takes everything that was good about the original and stuffs it into a 1 hour package. Seriously, its every good set-piece moment one after another. Its fun, although I would have enjoyed it more if it was a bit longer and had a slower pace. Oh, and robin's basically the same as Batman just with different gadgets.