I remember some time ago that, at least some of the Major rings from Simon's shop in Verbobonc would stop working after awhile. I didn't (and still don't) understand the limits in the number of spells the rings were able to cast. Now, reading the description of the rings, it says you should be able to cast 10 spell levels worth of spells from the school of magic the ring belongs to (i.e. Ring of Illusing allows you to cast 10 levels of illusion spells). What is supposed to happen once the 10 levels are up? Is it ten levels per day, or ten levels and then the ring doesn't function anymore? Also, if there is supposed to be a limit to the rings (they stop working altogether after the right conditions are met for this to happen) I'm having a hard time reaching it using the ring of Illusion. I cast Phantasmal killer 10 times (killed someone with it 2 of those 10 times), mirror image once, displacement 6 times, and was still able to cast using the ring.