I wouldn't use GTB. Nice priests can't heal/bless you, and you can't run through their sanctuary. Also, you use up enough SP as it is without GTB.
I like Ancient Mummy because it works well with Disguise card armor. You need to let the mob hit you once in a while to let Disguise card silence them and if Ancient Mummy then autocasts Signum Crucis you get to beat the snot out of the mob that has a bit less defence.
Once you get Spring Rabbit Clip, the 40% reduction from Khalitzburg isn't really that important anymore.