I spotted this for just 50p during a charity shop trawl and didn't realise it was Mind Games when I bought it, now I'm really pleased a grabbed a copy because the UK, hands down, has the best cover. Why have a big face when you can have all this gothic goodness? Sister Assassin is such a cool title too. 
 In a world of books with dainty heroines, (this is starting to sound like a movie voiceover), Sister Assassin is a pretty brutal book with Fia frequently getting bloodied, shot, even tasered at one point. I really liked Fia, all her flaws and quirks made her a perfect character, even if she was severely damaged. She's constantly sarcastic, which is guaranteed to make me love you forever in any situation. 
 Annie on the other hand I never really 'got'. She felt a little... cardboard. The chapters switch from Fia's to Annie's point of view but Annie really didn't fit well in the story for me. While Fia was the beautifully flawed character with all these emotions, Annie was just... there. The blind sister who sees stuff. It might just be me but her character development didn't feel as strong as Fias. 
 The concept is an old one - people with supernatural abilities but the way the story was presented was quite unique. Fia and Annie are both trapped by the Kessler School who threaten to kill Annie if Fia doesn't do what they want her to. The abilities are all to do with the mind - feeling emotions, reading thoughts, that sort of thing. No flying or laser eyes, yet anyway. 
 The was a fun twist to the end of the story where I was thinking, is she really going to do it? It either showed just how clever Fia is or just how crap Annie's abilities are, I'm not sure which. I'm really looking forward to the sequel though, I need more Fia in my life. She puts the sass in asSASSin. (I'm proud of that don't judge me)