Red Mantis Assassin's use Cha not Int for spells
 

I used the rules according to herolab, however as I have learnt from the developers of the game that was a typo and it was more of presence than intellect so the stats in the book are correct but not the use of spells being int based:

http://paizo.com/paizo/messageboards...stion&page=1#5

The Red Mantis Assassin was originally added in the 3.5 World Guide. Since we're about a month from the release of the ISWG, and I'm presuming this class will be updated in that book, I'm going to hold off on fixing the 3.5 version - I'd rather just update it to the Pathfinder version.