Catwoman's not too bad in the combat challenges as it's really easy to build combos with her. Of course, once you get to the ones that have Titans in them it gets a lot harder as she can't ride them around and use them to smack people.
Her stealth challenges are just...ugh.
I really need to get back to Arkham City and finish up NG+ and the challenges, but I've got way too many other games to play.
And congrats on the Platinum. I'm aiming to get all of the achievements once I get back to the game. Hopefully I can do that soon.
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Gamertag-Murphiroth
Pokemon Black-1978-9490-1161