Actually both me and Usagi suggested it. It would be best if you could give your pet a command whether to try and take melee damage for you or not. Aramon clerics wouldn't want to camp for xp with a blocking pet because of their nerfed heal-other. Likewise the lich pets which cast all the way down to 1hp, so having them block attacks is a little stupid.

Now that I think of it, maybe it would be best if all pets (all classes) healed for 1/2 the normal amount, so that using them for blocking damage would always be less effective than having your player char do the tanking. but, they would still be useful vs tough aggro rooms and such. Thoughts?

oh and another thing, it only makes sense for pet blocking to work if you (the conjurer) are wielding a missile weapon, or not attacking the same (blocked) mob in melee.