viconia as nightcloak of shar and spell failure

[Guest Usurper]

I just changed Viconia in a BiG World Project game to a Nightcloak of Shar via Shadowkeeper. (I had not set this option during installation.) She was level 6 at the time. I followed the regular procedure of deleting everything special about her character and reducing her to level 0, and then leveling her up when she had the new class. Then I re-put in all of her xp and got her back up to level 6. However, now when she casts spells, she seems to undergo a lot of spell failure. She was wearing a studded leather +1 during the fight, so I took it off and had her cast more spells, but she still seems to experience spell failure. I don't understand what could be causing that and I"ve never seen this before. Is there something about a nightcloak of shar that creates a chance for spell failure?

[Guest Guest]

ok, nevermind, it was apparently due to an item I had given her: the Gauntlets of the Drow. It says the only effect is to have one extra attack per round, but when I put it on her she starts failing her spells.