Yup. For one spell once per day. To relativise, they are level 14 now. So it's not like they didn't had access to 15 different game breaking options. But I was sure that the character would die... for like 1 session before one of the 5 ways of bringing someone back to life would be used.

It is hard to make a decent challenge for high leveled players. If I can make them nervous, even if they win easily I call it a DMing win. And I certainly managed that last night so I'm fine with it.