I'm playing Seoni so spells are pretty high on my mind.
My favourite spell so far is definitely Augury. I recently played Augury, chose Monster as my card type, turned over three monsters and placed all three on the bottom of the deck. I now have a relatively safe location to explore until I find the henchman or villain.
Detect Magic is good in a similar way. When you find a monster beyond your capability at that time you can leave the location to someone else. Same with a great boon, such as longbow +1, that you can't acquire yourself, nor do you want it, but let Harsk know where it is and he will be happy to move across.
